Is your Android smartphone not going into deep sleep? It will be draining battery at a considerable rate if it is running the CPU at 300MHz. Use the CPU Spy to check whether it is going to deep sleep when u are not using it.

Try the following if it is not going to deep sleep
Option 1
1. Power off and remove your battery out for 2 mins.
2. Fix the battery back and power on it.

Option 2
1. Reboot into recovery mode
2. Wipe the cache
3. Exit and reboot the system

Leave a comment on whether this help you to stop the battery drain.