2 windows clients, >150 samba connections?

i have 10ish mac users and 2 windows users connected to a 10.3 server. the macs are connecting via AFP, and the mac users have local/netinfo user accounts on the server. the windows users are authenticating through our NT domain, and connecting via smb. the two windows (one on 2000 and one on XP) users are somehow generating upwards of 150 active samba connections, which grinds the server to a shuddering halt (which is why i've limited the samba connections to 50 now). much as i enjoy seeing the CPU graph hovering near 100... anyhoo, the server itself is set as a "domain member" of the NT domain (no, we're not up to active directory on the windows side yet) and is registering with the WINS server. per joel's recommendation, i have turned on strict locking on the share in question, and turned off oplocks, but the situation remains - the longer the windows clients are connected, the more zombie connections are created, and thus more swap and cpu is eaten up. has anyone else seen this behavior in samba before? i used to run samba 2ish on a linux box with the same set of mac and windows clients (the macs connecting via smb as well, then) and never had this particular problem come up. i'm hoping i can pin it on the NT domain somehow, so i can expedite its replacement with active directory/ldap, but any ideas would be greatly appreciated at this point.