Glock will quickly fix the problem if it is persistent. Just give 'em a call. I've always found them to be extremely friendly and attentive. I'd speculate that the Glock Customer Support job is akin to the Maytag repairman job -- they don't get many calls, so they're always eager to talk to people
P.S. - The Glock owners manual tells you to not wipe off the copper lubricant :)