> Our company just acquired another which was using the Elementool tracking system.
> We want to drop Elementool and merge the bug database from Elementool into ours.
> What format do we need to export Elementool in so we will be able to import the bugs
> into Mantis? How do we import into Mantis without loosing all our existing bugs in Mantis?
Checkout the new FAQ, it is still work in progress:
You can use “Migration from Custom Bugtrackers” approach or develop a script that imports data from ElementTool to Mantis. Similar to what is available for Bugzilla, GNATs, and TaskVision.