10.5.8 binding issues to Windows SBS 2011

I am running OS X 10.5.8 and am attempting to bind the AD to our Windows SBS 2011 server. I get all the way to step 5 (after clicking Bind) and then a popup appears stating that there was an "Unknown Error" -- how can I find out what the error is? There is no code referenced. The Active Directory Domain is correct and the Administrative (under Advanced Options) is also correct.