I have been extensively playing around with various email clients. I even tried to build thunderbird but it failed. My conclusion is that evolution, which is installed by default in MintPPC64, is not a good alternative as it segfaults. In other words, this program is unusable. I tried claws-mail but I don’t like the way the mails are presented: there is too little space in between the various mails, it looks very clogged. I then turned to sylpheed. It is basically the same as claws-mail but it looks a lot better. The program works well and I can now recommend this program as default email client. It has been built successfully by bulldd for a while now, so I can safely add it to the preseed file for automatic installation. I will therefore replace evolution by sylpheed in MintPPC64.