[Samba] Windows client hangs running .exe from Samba share

[CJ]

I'm running Mac OS X Server 10.4.1, smbd --version 3.0.10.

I have been using it for a couple years running roaming profiles for  
Windows 2000 clients with few problems.

It was time to reinstall the client machines with new applications,  
keeping Win2K as the client operating system.  I consulted my notes  
and adjusted the local system policies to exclude certain folders  
from the roaming profiles, map certain groups to local Administrators  
and Power Users, etc.  All's fine.

The users can log into the new machines fine, roaming profiles are  
working, and reads and writes to the network shares seem fine.

But if someone tries to run a small application file from a network  
share (examples being putty.exe and whoami.exe), windows explorer  
hangs - won't respond to any more input, the quick launch icons and  
task bar buttons disappear, and the machine must be rebooted.  I can  
copy putty.exe from the network share and run it from the local drive  
just fine.  Users on the client machines I haven't rebuilt yet can  
run it from the share without issue.

I really don't know what in Windows could be causing this and am  
wondering if anyone else has ever seen this.

Thanks.