do not use the wysiwyg editor. development of this feature is not finished and delivers such kind of message.
another point may be within syntax.php around the line 1314:
Replace the following line:
if(strlen(DOKU_BASE) < strlen(DOKU_URL)) $sFilename = DOKU_INC."lib/plugins/issuetracker/xsEditor.js";
by this one:
if(strlen(DOKU_BASE) < strlen(DOKU_URL)) $sFilename = DOKU_URL."lib/plugins/issuetracker/xsEditor.js";