zlib problem

[sebe]

i noticed when i enable zlib compression the forum loads the page and all, but it kinda stalls at the end and 'opening page' in the status bar appears for like 30 seconds... these are the values i use on my server:

zlib.output_compression 1
zlib.output_compression_level 1

i disabled vbulletin's gzip feature, and still doesn't work correctly..