trusting your own keys

[Thomas Zander]

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I recently sent an email, and tried to read that myself. The email was signed
and I surprisingly got the following message:

gpg: Signature made Wed Jul 28 16:50:13 1999 MEST using DSA key ID 0A0588D5
gpg: Good signature from "Thomas Zander <zander@earthling.net>"
gpg: WARNING: Using untrusted key!

How can I not trust the key combined with my secret key?

I tried the edit-key, and set the trust to 4 (full), so what am I doning wrong?

Thanx.
- --
Thomas Zander                                                zander@microweb.nl
History repeats itself, it has to, nobody ever listens         gpg-key:  0588D5
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