I'll either have to find some way to install a local pear (not something I want to do) or I'll have to bundle a version(always fun for updates and bugfixes). But I suppose I'll need to php5 it anyway so it won't kill me.
Opera turned out to be a REAL headache. When Opera gets a Content-Type header it doesn't understand - instead of leaving the data as is it like...I don't know...turns it to a binary file or something? In any case the information becomes horribly garbled. The problem is HTML_AJAX uses Content-Type to decide what serializer/unserializers to use on the data. So opera gets a BIG FAT HACK that detects window.opera (always present on 7.6+ - which is when xmlHttpRequest support was introducted anyway) and changes the content-type to text/plain and adds an x-content-type header with the real type to use. What a mess! I reported a bug but it's not like I can track it or anything. You'd think they'd at least let you see your own bugs... Ok, enough of the opera rant. I'm sure that other browsers will introduce weird strange bugs that boggle the mind, but so far everything's working for me.