| | Re: BBM Saves Old History Only to a certain size limit?
The default storage location is in the BlackBerry's internal memory. If you changed it to the memory card and have 100MB of space left, that shouldn't be the problem then.
If your internal memory drops below 10MB or 12MB the BlackBerry might be clearing chats to free up this memory. It's needed for the OS to run properly. Text messages, calendar events, chats, and even email messages can be lost to critically low internal memory.