mysql string comparison

[bunnytail]

Hi,

I have string in a field like theses: rel-1-0, rel-2-0, rel-3-0,
rel-21-0.....

if comparing them in this way: select 'rel-3-0'>'rel-21-0';
Mysql will return "1" as true, this is false in our knowledge.
I wonder if there is a way to order such string inside mysql so that
rel-3-0 < rel-21-0?

cheers,
sheng