Thunderbird Enigmail pEp creates new key pairs

Hi,

I installed the Enigmail addon on Thunderbird and it created a new Key Pair for each of my email accounts.
I exported those Keys. On a second computer, I also want to use those keys. After I installed the Enigmail addon on the second computer, new key pairs were created.
I imported the Key pairs from the first computer and deleted the newly created keys.
Hower, when I restart thunderbird, for each account a new key pair is created again. So I end up with to key pairs for each account on the second computer.
How can I prevent Enigmail pEp from creating new key pairs and use the imported ones?

Any suggestions welcome.
Thanks, Exus.

Enigmail 2.0.8 with thundebird on arch linux.

The imported keys don't show a trust level, the newly created ones that I delete and that reappear show trust level ultimate.

I changed the trust level to ultimate of the imported keys and deleted the newly created ones. After Thunderbird restart I get again new key pairs.