Use a different column type in your table definition. You can use BLOB or TEXT (they're interchangeable) to extend the character limit. You can prefix either of these to better define the max number of characters as follows:
TINY gets you 2^8
[no prefix] gets you 2^16
MEDIUM gets you 2^24
LONG gets you 2^32
Subtract 1 from any of the above and you have your limit.
So, TINYTEXT would result in a 255 character max.
Hope this helps,
brendanc@icehouse.net