diff --git a/src/canvas.js b/src/canvas.js
index cc6d50ded..32c171216 100644
--- a/src/canvas.js
+++ b/src/canvas.js
@@ -1196,20 +1196,20 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
     // Marked content
 
     markPoint: function CanvasGraphics_markPoint(tag) {
-      TODO('Marked content');
+      // TODO Marked content.
     },
     markPointProps: function CanvasGraphics_markPointProps(tag, properties) {
-      TODO('Marked content');
+      // TODO Marked content.
     },
     beginMarkedContent: function CanvasGraphics_beginMarkedContent(tag) {
-      TODO('Marked content');
+      // TODO Marked content.
     },
     beginMarkedContentProps: function CanvasGraphics_beginMarkedContentProps(
                                         tag, properties) {
-      TODO('Marked content');
+      // TODO Marked content.
     },
     endMarkedContent: function CanvasGraphics_endMarkedContent() {
-      TODO('Marked content');
+      // TODO Marked content.
     },
 
     // Compatibility
diff --git a/src/core.js b/src/core.js
index 409ae060d..2b9481041 100644
--- a/src/core.js
+++ b/src/core.js
@@ -52,8 +52,16 @@ function getPdf(arg, callback) {
   if ('progress' in params)
     xhr.onprogress = params.progress || undefined;
 
-  if ('error' in params)
-    xhr.onerror = params.error || undefined;
+  var calledErrorBack = false;
+
+  if ('error' in params) {
+    xhr.onerror = function errorBack() {
+      if (!calledErrorBack) {
+        calledErrorBack = true;
+        params.error();
+      }
+    }
+  }
 
   xhr.onreadystatechange = function getPdfOnreadystatechange(e) {
     if (xhr.readyState === 4) {
@@ -61,7 +69,8 @@ function getPdf(arg, callback) {
         var data = (xhr.mozResponseArrayBuffer || xhr.mozResponse ||
                     xhr.responseArrayBuffer || xhr.response);
         callback(data);
-      } else if (params.error) {
+      } else if (params.error && !calledErrorBack) {
+        calledErrorBack = true;
         params.error(e);
       }
     }
diff --git a/src/fonts.js b/src/fonts.js
index c955c4d1a..7b2dfbd4a 100644
--- a/src/fonts.js
+++ b/src/fonts.js
@@ -3391,8 +3391,8 @@ var Type1Parser = function type1Parser() {
       '1': 'vstem',
       '2': 'hstem',
 
+      '6': 'endchar', // seac
       // Type1 only command with command not (yet) built-in ,throw an error
-      '6': -1, // seac
       '7': -1, // sbw
 
       '11': 'sub',
@@ -3422,6 +3422,43 @@ var Type1Parser = function type1Parser() {
 
   var kEscapeCommand = 12;
 
+  // Breaks up the stack by arguments and also calculates the value.
+  function breakUpArgs(stack, numArgs) {
+    var args = [];
+    var index = stack.length - 1;
+    for (var i = 0; i < numArgs; i++) {
+      if (index < 0) {
+        args.unshift({ arg: [0],
+                       value: 0,
+                       offset: 0 });
+        warn('Malformed charstring stack: not enough values on stack.');
+        continue;
+      }
+      var token = stack[index];
+      if (token === 'div') {
+        var a = stack[index - 2];
+        var b = stack[index - 1];
+        if (!isInt(a) || !isInt(b)) {
+          warn('Malformed charsting stack: expected ints on stack for div.');
+          a = 0;
+          b = 1;
+        }
+        args.unshift({ arg: [a, b, 'div'],
+                       value: a / b,
+                       offset: index - 2 });
+        index -= 3;
+      } else if (isInt(token)) {
+        args.unshift({ arg: stack.slice(index, index + 1),
+                       value: token,
+                       offset: index });
+        index--;
+      } else {
+        warn('Malformed charsting stack: found bad token ' + token + '.');
+      }
+    }
+    return args;
+  }
+
   function decodeCharString(array) {
     var charstring = [];
     var lsb = 0;
@@ -3464,6 +3501,12 @@ var Type1Parser = function type1Parser() {
             // pop or setcurrentpoint commands can be ignored
             // since we are not doing callothersubr
             continue;
+          } else if (escape == 6) {
+            // seac is like type 2's special endchar but it doesn't use the
+            // first argument asb, so remove it.
+            var args = breakUpArgs(charstring, 5);
+            var arg0 = args[0];
+            charstring.splice(arg0.offset, arg0.arg.length);
           } else if (!kHintingEnabled && (escape == 1 || escape == 2)) {
             charstring.push('drop', 'drop', 'drop', 'drop', 'drop', 'drop');
             continue;
@@ -3471,25 +3514,17 @@ var Type1Parser = function type1Parser() {
 
           command = charStringDictionary['12'][escape];
         } else {
-          // TODO Clean this code
           if (value == 13) { // hsbw
-            if (charstring.length == 2) {
-              lsb = charstring[0];
-              width = charstring[1];
-              charstring.splice(0, 1);
-            } else if (charstring.length == 4 && charstring[3] == 'div') {
-              lsb = charstring[0];
-              width = charstring[1] / charstring[2];
-              charstring.splice(0, 1);
-            } else if (charstring.length == 4 && charstring[2] == 'div') {
-              lsb = charstring[0] / charstring[1];
-              width = charstring[3];
-              charstring.splice(0, 3);
-            } else {
-              error('Unsupported hsbw format: ' + charstring);
-            }
-
-            charstring.push(lsb, 'hmoveto');
+            var args = breakUpArgs(charstring, 2);
+            var arg0 = args[0];
+            var arg1 = args[1];
+            lsb = arg0.value;
+            width = arg1.value;
+            // To convert to type2 we have to move the width value to the first
+            // part of the charstring and then use hmoveto with lsb.
+            charstring = arg1.arg;
+            charstring = charstring.concat(arg0.arg);
+            charstring.push('hmoveto');
             continue;
           } else if (value == 10) { // callsubr
             if (charstring[charstring.length - 1] < 3) { // subr #0..2
diff --git a/test/pdfs/issue818.pdf.link b/test/pdfs/issue818.pdf.link
new file mode 100644
index 000000000..c7ed0236a
--- /dev/null
+++ b/test/pdfs/issue818.pdf.link
@@ -0,0 +1 @@
+http://www.effi.org/system/files?file=effi-siv-251110.pdf
diff --git a/test/test_manifest.json b/test/test_manifest.json
index ffcf10bed..1b372e906 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -633,5 +633,13 @@
       "pageLimit": 2,
       "link": true,
       "type": "eq"
+    },
+    {  "id": "issue818",
+      "file": "pdfs/issue818.pdf",
+      "md5": "dd2f8a5bd65164ad74da2b45a6ca90cc",
+      "rounds": 1,
+      "pageLimit": 1,
+      "link": true,
+      "type": "eq"
     }
 ]