I had to generate a new gpg-key pair, because to old one has expired. Using this ney key, each time signing a new email, I have to give the passphrase to a pinentry-qt4 dialogue. However, I am still using an older (not yet expired key) for my private mails. Using this key signing works without a passphrase entry.

Is there a way to overcome the passphrase entry for each mail again?