In my dynamic web project in eclipse, I have jQuery in my js source folder. For some reason, Eclipse is not handling it correctly and interpreting many lines as errors in the standard jQuery file (even though I have the javascript development tools installed).

I have found that I can leave the JavaScript Validator enable and ignore specific files by adding a suitable exclusion pattern e.g. **/jquery*.js to the JavaScript/Include Path/Source/Excluded group (Project->Properties->JavaScript->Include Path->Source).