This is repost of a thread from TeX.sx[1].

OP created his own syntax highlighting environment using listings package. He used escapechar feature to insert LaTeX macros inside this environment. Unfortunately, escapechar call the same macros as tex4ht use for inserting end and start tags of listings environment, `\lst@EnterMode` and `\lst:EnterMode` respectively, so these tags are inserted into the code.

I added new conditional to test whether these macros are used for the first time in current listings environment.

Patch agains tex4ht-4ht.tex literate source is attached.

[1] http://tex.stackexchange.com/q/188322/2891