Column in percentage

I want to set the column width to be in percentage.
Kindly let me know how to do this.

Thanks.

The % width is not yet supported.

I have a grid called from 2 diferent sides ... When you click the first option you can see a grid with 3 columns, but when you click the second option you can only see 2 columns.
The problem is: The 1st option show you 3 columns and the second column has a lot of text in it. BUT ... the second option with his 2nd column only show numbers.
The thing is, in both case, the column with is too big. To the 1st option is ok, because it show large text (maybe 200px), so i need to know how can i resize automatically the 2nd column when it show numbers (DB IDs).

If anybody can help me out i would really appreciate it!

regards

By the way, this is the CSS line that set the static width to the column.

.active-column-<?=$n++;?> {width: 275px;}

Maybe i need to change that value from JS when it needed but i dont know how to do that ... ill google it, but if anybody can help me out, would be just great!

thanks again