Modifying selection in the dropdown list

In开发者_运维百科 MOSS 2007, when you edit a web part, you can set width and hight using predetermined units of measure from the drop down list.

I want to find out where do these values come from. Are they somewhere in the database? I want to be able to modify the selection to include percent (%).

these values are stored in format of xml(webpart description file) and these are webpart instance dependent and stored in content database. as far as converting height and width from pixels to % is concerned you would have to create a custom new tool part and remove the existing one from webpart tool part