in the lastest version an incoming, PGP singned email causes the mail to get stuck in the SMTP spool, with state (red X) and Error.
Here are the relevant lines from smtp.log, whenever this happens:
2014:11:30-17:16:37 MYUTM exim-in[7793]: 2014-11-30 17:16:37 SMTP connection from [a.b.c.d]:19783 (TCP/IP connection count = 1)
2014:11:30-17:16:38 MYUTM exim-in[11307]: 2014-11-30 17:16:38 H=*.org (mail.*.org) [a.b.c.d]:19783 Warning: mydom.com profile excludes greylisting: Skipping greylisting for this message
2014:11:30-17:16:38 MYUTM exim-in[11307]: 2014-11-30 17:16:38 [a.b.c.d] F= R= Verifying recipient address with callout
2014:11:30-17:16:40 MYUTM exim-in[11307]: 2014-11-30 17:16:40 1Xv7At-0002wN-0S DKIM: d=*.co.uk s=default c=relaxed/simple a=rsa-sha1 [verification succeeded]
2014:11:30-17:16:40 MYUTM exim-in[11307]: 2014-11-30 17:16:40 1Xv7At-0002wN-0S ctasd reports 'Unknown' RefID:str=0001.0A0C0201.547B42E8.0083:SCGSTAT1542435,ss=1,re=-3.999,recu=0.000,reip=0.000,cl=1,cld=1,fgs=1024
2014:11:30-17:16:40 MYUTM exim-in[11307]: 2014-11-30 17:16:40 1Xv7At-0002wN-0S
So, mail arrives, 10 min later it is stuck in the spool as error and for every affected mail in the spool, an emailenc process is causing high CPU load, so I have to kill them manually and delete the mails from the spool, with data loss, of course [:(]
top - 01:10:32 up 4 days, 19:07, 1 user, load average: 8.25, 7.87, 7.79
Tasks: 216 total, 9 running, 205 sleeping, 0 stopped, 2 zombie
Cpu(s): 13.0%us, 86.9%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.1%si, 0.0%st
Mem: 4055720k total, 3634284k used, 421436k free, 130100k buffers
Swap: 4194300k total, 337328k used, 3856972k free, 1442380k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
11317 root 20 0 5404 832 760 R 59 0.0 1135:05 emailenc
22135 root 20 0 5404 1080 760 R 58 0.0 501:31.38 emailenc
31883 root 20 0 5404 1116 760 R 58 0.0 1059:48 emailenc
954 root 20 0 5404 776 752 R 57 0.0 5820:12 emailenc
7964 root 20 0 5404 804 760 R 57 0.0 2356:07 emailenc
25750 root 20 0 5404 728 716 R 55 0.0 2882:50 emailenc
11182 root 20 0 5404 792 768 R 52 0.0 4328:43 emailenc