How can I make my text message inbox bigger?

I have a Samsung Tocco Ultra and the inbox is only about 240 messages. I've never been a big texter so this was never a problem until the last few days in which I have probably received half to two thirds of that number of texts. I like to save interesting ones so I hate going through and deleting them. Can I allocate some memory card storage to my inbox or something?|||No you cant|||Bigger memory card? my phones got a 4gb memory card and i must have say 12,000 on their and never deleted any.|||as far as i know its not possible to make the text message inbox bigger