I don't really know what that problem means, but i always got erros when trying to upload a very large database so now I use bigdump.
download here:
http://www.ozerov.de/bigdump.php
Open the file with a text editor, add your forum database login info etc then just upload the .php file to your ftp ( any location ).
upload your forum's .sql file to any directory you want ( if you do it outside of public_html it will be more secure ) and remember to edit the path of the .sql file in the bigdump.php..
then run the script and done, it will import the backup to your database very fast ..