smb mount login problem with "%" (percent sign) in password

After upgrading to 10.5 (and then 10.5.1) from 10.4, couldn't mount previously mountable Windows 2000 SP4 server machine using SMB using the same account name and password. This server has ftp and afp access also, which work fine. Other accounts on server work fine, as this did pre-Leopard. Created other accounts with different passwords on server, which worked, however, noticed that the account with a problem used a password with a '%' (percent sign) in it. I tried using other characters in its place, e.g., ~ ! @ # $ ^ & * ( ) + = { } | \ / ? ; " ' and 'space' -- all others worked fine. I also tried a couple of different passwords with different results:

1. Password: J4p%36uY Result: 1st time prompt for user name and password, for the result would get the 'Sorry, you entered an invalid username or password'; 2nd time get the message that my '. . . account has expired'. On the Win2K server, the account would be locked out (which was set to lock out after 5 password tries!)
2. Password: bbb%sss1 Result: 'Connecting to Server' window indicates connecting via smb to machine but you can't cancel this window, it doesn't time out (at least after 10min!) and I had to relaunch the Finder to close it.

I also setup another server using Tiger workstation and did a Windows share. The Leopard client also would not work connecting to this server(although there is no notion of locking the account out after xx number of times trying!)

I know I'm shooting in the dark on this, but could anyone else verify this?

Our *nix god here referred me to the following google searchable items:

format string buffer overflows
scanf
printf

We dug around a bit on:
http://www.opensource.apple.com/darwinsource/10.5/smb-344/

but maybe someone out there could shed more light on this before we spend too much time on this? or is there a better way to file this as a bug with Apple internal development?

Thanks!