Gentlemans,

is it possible to use kmail 1.13.7 (or circa) with modern KDE (4.12+)?

i'm still have to use kmail 1.13.7 and so ancient kde (4.6.5), because kmail 4.12.3 is seems to be unusable (real mail archive, work + home, 20+multilevel folders, some thousand mail + mail lists. Old mail was archived and than re-imported for kmail 4.12.3). Symptoms:

1) after starting of kmail, computer is unusable up to 40 minutes or more: LA is >25 for mysql process (Athlon II X4, 4GB RAM, X86_64 Linux, local maildir/mailbox folders for pop3 mail),

When system relax,
2) opening any mail folder needs from 60 seconds up to 20 minutes!!!!!!!!!!!!!!!
Even gmail's imap account opens 10 - 40 seconds.

3) when new mail arrives, LA may increase up to 5 or more for some minutes.

If watch Akonady console, one can see very rocket productivity in 0.1 -- 1 mail per second (oh yes, multiplieng for thousand mails... )

4) there is no way to find a letter, is full indexing is switching off, but full text indexing in real mail archive... i suggest, process will be completed in 2017

Possibly, kmail was the best mail client, but last 4 years it's deplorably unusable.

So is there any gentle way to use kmail 1.13+ in recent KDE's environment? Or is there any way to export mail structure for Thunderbird or some another clients?

Sorry, but i'm in Despair. Absolutely apparently, the idea to store mail information in SQL was more than haplessly, it was destructive and there is no more any hope to make it efficient.

Loss of mail archive (depth from 1995) is unacceptable too.

PS: using mariadb-client-5.5.34

I would suggest you try KDE PIM 4.13 (there's a live CD on susestudio.com if you don't want to risk installing it on your system). The underlying search framework has been overhauled and at the same time a lot of optimization has been put in.

I never had issues with PIM but I must say that 4.13 is definitely much better than before.