Google Analytics stopped working – fix?

On July 21, Google Analytics stopped working on my WP 2.6 blog. When I logged in and looked at the Analytics page in the plug-ins admin area, I discovered that my Analytics account number went missing, and there was a letter “a” inserted in every other field. So I re-established my account number, corrected the other fields and saved my changes. That was almost a week ago, and Analytics is still showing 0 visits. Is this a WP 2.6 upgrade issue or what? Anyone else having this problem?