If I use EXT-JS 2.0 GPL licensed library in my web site which may be
considered commercial website but does not charge money to its visitors,
I do not have to buy commercial license?

In my scenario which I think is typical for most users of EXT-JS, I am not in
the business of developing and distributing tool kits or software development libraries
to redistribute EXT-JS. I am simply planning to use some of the widgets and ajax features in in EXT-JS in the web application on the website (under development and not released) . The
EXT-JS library files would be served in minified form to the client.

I looked at the offical GPL web page but it does not make this use case clear at all.

I have the same above question regarding the use of Ext GWT 1.2 in above scenario.

I would appreciate any knowledgeable person(s) to answer this question as I could not find clear answer by googling.