This has nothing to do with Google blacklisting Gmail accounts. What's happened is your Market DB has gone out of sync from swapping your account between phones with different apps installed. The DB glitches if your phone and/or account says an app is installed but the apk isn't in /data/app.
It's a known bug on Google Support forums. To avoid I make sure I only have my Google account signed in on one phone at once and do not swap back. Always perform a wipe when changing ROMs. Keeping backups of your APKs with AppManager and using Recovery to both "wipe dalvik-cache" and "fix apk uid mismatch" could be used to solve this, maybe not.
We've all been running rooted phones for ages, Google doesn't care about it.
Current: Samsung Galaxy S2 I9100 + CM7 Nightly
Current: Samsung Galaxy Tab 10.1 P7510 + root
Previous: T-Mobile G1, HTC Magic 32B, Google Nexus S I9023