I finally found a fix. I’ve been getting the “Low on space – phone storage space is getting low” message on my HTC Incredible often. I get this message even when I have hundreds of MB free. I’ve tried ignoring the message (no other problems really come up). I’ve tried deleting applications– that sometimes works, sometimes doesn’t. I think I’ve figured out what it is. The fix isn’t permanent, but it does clear the message.
Please read and understand the whole thing if you plan to do what I’ve done below. It’s involves deleting data– you may lose important information.