Hi Paul,
I cannot see anything on that both in the administration log and in your account. If you could log on normally, then it would seem that it was an access attempt by a third party, with maybe your registered e-mail address having been compromised somewhere.
Maybe you could check the e-mail header info if the mail actually came from LAF? The sender e-mail should be forum@lead-adventure.de.
I'll forward this to the tech chaps so they might take a closer look.