one error while converting vbulletin 3.8.4 to smf 1.1.0 please see its urgent

[Hell Raiser]

Converting posts (this may take some time)... Successful.
Converting polls... Successful.
Converting poll options... Successful.
Converting poll votes... Successful.
Converting personal messages (step 1)... Successful.
Converting personal messages (step 2)... Successful.
Converting topic notifications... Successful.
Converting board notifications... Successful.
Converting smileys... Successful.
Converting attachments... Successful.
Converting avatars... Successful.
Recalculating forum statistics... Successful.

Notice: Undefined variable: to_prefix in /home/syshacke/public_html/convert.php on line 1821
Unsuccessful!
This query:
REPLACE INTO settings (variable, value)
VALUES ('conversion_time', 1253424084),
('conversion_from', 'vbulletin37_to_smf.sql');
Caused the error:
No database selected

Can anyone tell me how to fix it 

[JBlaze]

As long as this message comes up, "Recalculating forum statistics... Successful.", the conversion was successful.

Also, see Common conversion errors.

[Norv]

Yes, please ignore that last error. It's a little bug in the converter actually, which has nothing to do though with the conversion itself: congratulations on a successful conversion!

[Hell Raiser]

Thanks Norv for clearifying me, this was my first conversion for my freind.I am encouraging them for smf  .