in reply to the axml parser v3.4
First of all, your file writes are going to collide if two instances of your program run at the same time and try to write the same file. You need some kind of race-free file locking mechanism to prevent that. See perlopentut for a good starting point.
Your code is susceptible to the poison null byte in the request parser. Ouch! Google for that. And while you're at it, use CGI::Simple or CGI to get away from the many potential failures that exist in your request parsing code.
If you take GrandFather's very fine advice and use the strict pragma, your code will throw an ugly Error 500 if a file open fails. You should check that the opens succeed before trying to read or write a filehandle, and fail or recover gracefully if the open fails.
There are three things, I'll leave some for the other fine monks to pick on.
And again, don't be afraid of CPAN. Wouldja rather learn to work with CPAN, or release code that makes you look like a dork?