Invalid SQL problem

[vexxy]

I've recently started to get this invalid SQL issues:

Invalid SQL:

SELECT *
FROM style
WHERE (styleid = 2 AND userselect = 1)
OR styleid = 2
ORDER BY styleid ASC
LIMIT 1;

And the MYSQL goes away, error 2006. It's not a particular script that does that, i've seen reports on attachments, on ajax.php etc. Can anyone tell me what's this error about and how can i fix it? I run on VB 4.1.7 and a dedicated box.

MY.CNF file:

max_connections=500
safe-show-database
connect_timeout=15
interactive_timeout=100
join_buffer=1M
key_buffer=768M
max_allowed_packet=32M
max_connect_errors=20
myisam_sort_buffer_size=128M
read_buffer_size=12M
read_rnd_buffer_size=12M
sort_buffer_size=12M
table_cache=1024
thread_cache_size=128
thread_concurrency=8
wait_timeout=60
query_cache_size=256M
query_cache_limit=8M
query_cache_type=1
skip-innodb

i've also raised the wait_timout to 120, no success..same problems appear