If you're cutting Glutamine (by the way it's the same thing as L-glutamine) try to take it on empty stomach.
Glutamine Peptides are 3 times more absorbable than regular glutamine. And these can be taken w/ your shake since they don't compete w/ the other aminos (theoretically).
Glutamic Acid is 1/3 glutamine. I'm sure you've seen it on the ingredients of your whey shake. But like i said only 1/3 of it converts to glutamine.
I think all questions on glutamine have been answered on this thread... shit... it's hard to find a question not answered here on glutamine!