(gdb) bt
#0  0x00007f50f6eb7bc9 in __memp_fget () from /usr/lib/libdb-4.6.so
#1  0x00007f50f6e86827 in __db_doff () from /usr/lib/libdb-4.6.so
#2  0x00007f50f6e12dbc in __ham_del_pair () from /usr/lib/libdb-4.6.so
#3  0x00007f50f6e09f02 in __ham_quick_delete () from /usr/lib/libdb-4.6.so
#4  0x00007f50f6e6da3c in __db_del () from /usr/lib/libdb-4.6.so
#5  0x00007f50f6e7fbfc in __db_del_pp () from /usr/lib/libdb-4.6.so
#6  0x00007f50f7d0e377 in ?? () from /usr/lib/libaprutil-1.so.0
#7  0x00007f50f046368e in ?? () from /usr/lib/apache2/modules/mod_gnutls.so
#8  0x00007f50f046398e in ?? () from /usr/lib/apache2/modules/mod_gnutls.so
#9  0x00007f50f53f484d in _gnutls_store_session () from /usr/lib/libgnutls.so.26
#10 0x00007f50f53f4ab4 in _gnutls_server_register_current_session () from /usr/lib/libgnutls.so.26
#11 0x00007f50f53ee208 in _gnutls_handshake_common () from /usr/lib/libgnutls.so.26
#12 0x00007f50f53ee2a2 in gnutls_handshake () from /usr/lib/libgnutls.so.26
#13 0x00007f50f046249e in ?? () from /usr/lib/apache2/modules/mod_gnutls.so
#14 0x00007f50f0462837 in mgs_filter_input () from /usr/lib/apache2/modules/mod_gnutls.so
#15 0x000000000042cbcb in ap_rgetline_core (s=0x17f3378, n=8192, read=0x7fff00362c00, r=0x17f3348, fold=0, bb=0x17f4ac0)
    at /build/buildd/apache2-2.2.9/server/protocol.c:231
#16 0x000000000042d520 in ap_read_request (conn=0x1a32d08) at /build/buildd/apache2-2.2.9/server/protocol.c:596
#17 0x00000000004466d0 in ap_process_http_connection (c=0x1a32d08) at /build/buildd/apache2-2.2.9/modules/http/http_core.c:183
#18 0x00000000004403d3 in ap_run_process_connection (c=0x1a32d08) at /build/buildd/apache2-2.2.9/server/connection.c:43
#19 0x000000000044dc20 in child_main (child_num_arg=<value optimized out>) at /build/buildd/apache2-2.2.9/server/mpm/prefork/prefork.c:680
#20 0x000000000044df74 in make_child (s=0x1575968, slot=1) at /build/buildd/apache2-2.2.9/server/mpm/prefork/prefork.c:777
#21 0x000000000044ebb6 in ap_mpm_run (_pconf=<value optimized out>, plog=<value optimized out>, s=<value optimized out>)
    at /build/buildd/apache2-2.2.9/server/mpm/prefork/prefork.c:912
#22 0x0000000000425be5 in main (argc=3, argv=0x7fff003630f8) at /build/buildd/apache2-2.2.9/server/main.c:732