[jQuery] trim string

Hi, I have an array like this cat=(com12, com1, cop233, com1.1, sap-12-1) I want to take out all the numbers and "." and "-" signs the desire result is cat=(com, com, cop, sap) how can i do that please ?

[jQuery] $.trim(string) or string.trim()

mootools support syntax like this "string".trim() will jquery support such features in the future? thanks.