Crash when using HBCI setup wizard

[Robert Brückmann]

I have gnucash-1.8.12 with aqbanking 1.8.0_beta installed (gentoo
system). HBCI banking used to work - as far as I remember even with
1.8.12. But now it stopped working. GnuCash crashes whenever I click the 
'Start AqHBCI Wizard' button in the 'Initial HBCI Setup' dialog. A 
message box appears with: 'Application "/usr/bin/guile" (process 3235) 
has crashed due to a fatal error. (Segmentation fault)'.

The last lines of strace gnucash:
(...)
gettimeofday({1136820114, 636566}, NULL) = 0
write(4, "\2\30\4\0\350\4`\2\1\0\0\0\1\0\0\0=\0\4\0\350\4`\2\0\0"..., 
528) = 528
ioctl(4, FIONREAD, [0])                 = 0
poll([{fd=4, events=POLLIN, revents=POLLIN}, {fd=5, 
events=POLLIN|POLLPRI}, {fd=7, events=POLLIN}, {fd=6, events=POLLIN}], 
4, 3806) = 1
gettimeofday({1136820114, 819317}, NULL) = 0
ioctl(4, FIONREAD, [32])                = 0
read(4, "\4\1%#w&W\0G\0\0\0\350\4`\2\0\0\0\0\254\0\314\0f\0\16\0"..., 
32) = 32
gettimeofday({1136820114, 821585}, NULL) = 0
write(4, "\2\30\4\0\350\4`\2\1\0\0\0\1\0\0\0=\0\4\0\350\4`\2\0\0"..., 
584) = 584
ioctl(4, FIONREAD, [0])                 = 0
poll([{fd=4, events=POLLIN}, {fd=5, events=POLLIN|POLLPRI}, {fd=7, 
events=POLLIN}], 3, 0) = 0
gettimeofday({1136820114, 824843}, NULL) = 0
write(4, "\2\30\4\0\350\4`\2\1\0\0\0\1\0\0\0=\0\4\0\350\4`\2\0\0"..., 
1200) = 1200
ioctl(4, FIONREAD, [0])                 = 0
poll([{fd=4, events=POLLIN, revents=POLLIN}, {fd=5, 
events=POLLIN|POLLPRI}, {fd=7, events=POLLIN}, {fd=6, events=POLLIN}], 
4, 3617) = 1
gettimeofday({1136820114, 898961}, NULL) = 0
ioctl(4, FIONREAD, [32])                = 0
read(4, "\5\1~#\307&W\0G\0\0\0\350\4`\2\0\0\0\0\254\0\314\0f\0\16"..., 
32) = 32
open("/usr/lib/aqbanking/plugins/0/providers", 
O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY) = 10
fstat64(10, {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
fcntl64(10, F_SETFD, FD_CLOEXEC)        = 0
getdents64(10, /* 7 entries */, 4096)   = 216
stat64("/usr/lib/aqbanking/plugins/0/providers/aqhbci.xml", 
{st_mode=S_IFREG|0644, st_size=524, ...}) = 0
open("/usr/lib/aqbanking/plugins/0/providers/aqhbci.xml", O_RDONLY) = 11
read(11, "<plugin name=\"aqhbci\" type=\"prov"..., 1024) = 524
read(11, "", 1024)                      = 0
close(11)                               = 0
getdents64(10, /* 0 entries */, 4096)   = 0
close(10)                               = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
write(4, "\33\30\2\0\0\0\0\0 \0\2\0\0\0\0\0+\0\1\0", 20) = 20
read(4, 0xbfc53380, 32)                 = -1 EAGAIN (Resource 
temporarily unavailable)
select(5, [4], NULL, NULL, NULL)        = 1 (in [4])
read(4, "\1\1\201#\0\0\0\0\37\4`\2\0\0\0\0\0\0\0\0\31\0\0\0\340"..., 32) 
= 32
fork()                                  = 3282
waitpid(3282, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0) = 3282
--- SIGCHLD (Child exited) @ 0 (0) ---
exit_group(1)                           = ?


What went wrong?

Thanks in advance for any help!