I once took a look into the source of pdftohtml and porting it to Perl shouldn't be too difficult. ..

BUT

... it's based on a call to ghostscript which does the hard part.

And I doubt it can be done otherwise, I can't imagine anyone reimplementing PostScript in Perl.

So if

>  is configured not to allow the running of executables in cgi-bin. 

Then you should start looking for a new server.

I doubt it's possible to find an open solution not based on ghostscript.

(Except you find a Web service doing the hard part for you)

update

Well can you run executables outside cgi-bin ? And is ghostscript installed?