After a trip to the range a few months ago, I thoroughly cleaned my glock 22 with hoppes #9 and then ran a patch with break free lube down the barrel. The gun has been stored in a safe since then(with no golden rod-I know I need to get one). There is not a problem with moisture where the safe is located, yet when I inspected the gun today, it appears as if there is some rust beginnig to form in some of the grooves. There are also areas of the barrel that are greenish in color, yet appear to be clean otherwise. Any idea of what this could be? If this is rust, what is the be approach to remove it? Thanks.

Could very well be copper fouling. Try some of the copper removers and see if all that stuff comes out.

Well prof242, it seems you are right. Nothing more than copper fouling. Its amazing how much copper can accumulate in a barrel after as few as 75 rounds. Just cleaned it with wipeout: problem solved. Thanks.