You don't mention which utility you're using to check the signal strength.
I take them all with a huge pinch of salt. I can be in XP in my front room, some 20 feet from my wireless AP and Windows/IBM is telling me I have a 44% signal. Without moving anything I can reboot into Slackware or SuSE and get 80% or 90% signals.
Maybe the least inaccurate check is to use,
Agreed though, with your laptop sitting next to the AP you should be getting a better signal reading than you're getting. They always say put the AP as high up as possible, but away from walls if possible.
Let us know how you get on.