If Lehmanns cen represent Germany for this weekend competion, i believe Wenger would be the First one to observe and review on Lehmanns's form and confidence before Re-select him as Arsenal starting 11.
Anyhow, Almunia still have his oen standard and qualilty to compete with Lehmanns. That would defenitely be POSITIVE competion between both of them.
At this stage, you could see Lehmanns trying to recall everyone don't to Forget his contribution on "Arsenal 49 Unbeaten" season 03/04.