Well, you see, this is PerlMonks; not "ApacheMonks," and certainly not "psychicMonks." So it's fairly probable that we'll want to know about Perl issues... in detail.

So it might help us even more (to help you), if you were to reduce whatever Perl (there we go again; Perl!) code that you're using to "parse" and to "print" to the absolute minimum to demonstrate the error by producing the "garbage." and then, if you'll post that code here, along with input and output data (in each case, inside <code>...</code> tags) you'll find that you can provide quite a lot of detail.

You might also want to be very precise about whether "garbage" first appeared just as soon as you upgraded mod_perl; just as soon as you switched to 5.10 (at the same you upgraded mod_perl?) ... and, WAG, whether your current installation involved any other changes than those you've mentioned.