I am able to use ANdftp over 3G just fine but for AndSMB it does not work

I am using my external IP, I forwarded port 445 and used the same info for user name and pass word as I do for the ANDSMB over wifi and it just never connects.
Weird thing is when connected to wifi my AndSMB profile for 3G will work over wifi even though I used my external IP (this does not work for ANDFTP)
Please help.