possible tcp problem

[Andras Got]

Hi,

I'm using freebsd 6.1 and _sometimes_ (one for every ~30-40 minutes) I get mysql connect errors with 
permission denied. The mysql_connect returns error code 1, which is permission denied. The same 
happed to me when i tried to open a tcp connection between jails and it wasn't mysql related. The 
same happened sometimes this dawn with a sendmail host lookup. On the console I got the permission 
denied.

I don't really know what could cause this, but it's like a buffer gets full.

I use pf for filtering and nat. I checked pfctl -si which says there are ~800-1000 states, so it's 
well below the max 10000.

The question is that what could cause this thing and what should we try.

Errors:
sendmail[37085]: gethostbyaddr(IP) failed: 1
Can't connect to MySQL server on 'IP' (1)

netstat -m
298/812/1110 mbufs in use (current/cache/total)
286/396/682/25600 mbuf clusters in use (current/cache/total/max)
286/322 mbuf+clusters out of packet secondary zone in use (current/cache)
0/0/0/0 4k (page size) jumbo clusters in use (current/cache/total/max)
0/0/0/0 9k jumbo clusters in use (current/cache/total/max)
0/0/0/0 16k jumbo clusters in use (current/cache/total/max)
646K/995K/1641K bytes allocated to network (current/cache/total)
65610/107271/98848 requests for mbufs denied (mbufs/clusters/mbuf+clusters)
0/0/0 requests for jumbo clusters denied (4k/9k/16k)
0/0/0 sfbufs in use (current/peak/max)
0 requests for sfbufs denied
0 requests for sfbufs delayed
45726 requests for I/O initiated by sendfile
118 calls to protocol drain routines

Regards,
Andras