xcache.var_size is either 0 or too small to enable var data caching...

[Deimos]

Ok I have two forums
I'm moving them both to a windows based server, with php 5.2.6 and Mysql 5.0.51a

The first forum I setup, works aok, with no problems
It uses XCache

The second (main) forum has this error spammed down the whole page

Warning: xcache_isset() [function.xcache-isset]: xcache.var_size is either 0 or too small to enable var data caching in [path]\

The xcache settings are

xcache.var_count 4 4
xcache.var_gc_interval 300 300
xcache.var_maxttl 0 0
xcache.var_size 128M 128M
xcache.var_slots 8K 8K
xcache.var_ttl 3600 3600

So why on earth is it complaining about the var_size?