Virtual users & domains in Ubuntu 11.10: cannot set max quota more than 2147483647

I have followed the Virtual Users And Domains With Postfix, Courier, MySQL And SquirrelMail (Ubuntu 11.10) howto and noticed that I cannot set the user quota to anything more than 2147483647 bites. The 'quota' field in the 'users' table in the db is a int(10). How can I make it accept lager values?

 

...never mind me. Changed it to a bigint and it worked just fine.