After upgrading to PR1.2 the Jabber connection got a checkbox for "Secure
Connection only" and "Ignore SSL errors". The latter is checked by default.
However, if I untick that (which should be the default anyway, because it
undermines the users security because she can be man-in-the-middled trivially)
the Jabber connection can't be established. I receive "Network error". The
Debug Log is here:

Jul 27 13:29:15 Nokia-N900 telepathy-gabble[1719]: GLIB DEBUG tp-glib/presence
- tp_presence_mixin_simple_presence_set_presence: called.
Jul 27 13:29:15 Nokia-N900 telepathy-gabble[1719]: GLIB DEBUG tp-glib/presence
- check_for_status: Found status "available", checking if it's available...
Going to connect to jabberd.jabber.ccc.de:5222
Trying 217.10.10.196 port 5222...
Connection success (1).

SEND:
-----------------------------------
<?xml version='1.0' encoding='UTF-8'?>
-----------------------------------
*** b_written: 38
*** wrote 38 bytes
*** Sending stream header

SEND:
-----------------------------------
<stream:stream version="1.0" xmlns="jabber:client"
xmlns:stream="http://etherx.jabber.org/streams" to="jabber.ccc.de"
id="793100801484">
-----------------------------------
*** b_written: 136
*** wrote 136 bytes

RECV [171]:
-----------------------------------
'<?xml version='1.0'?><stream:stream xmlns='jabber:client'
xmlns:stream='http://etherx.jabber.org/streams' id='2587321471'
from='jabber.ccc.de' version='1.0' xml:lang='en'>'
-----------------------------------
*** Read: 171 chars
LM-PARSER: ATTRIBUTE: xmlns = jabber:client
LM-PARSER: ATTRIBUTE: xmlns:stream = http://etherx.jabber.org/streams
LM-PARSER: ATTRIBUTE: id = 2587321471
LM-PARSER: ATTRIBUTE: from = jabber.ccc.de
LM-PARSER: ATTRIBUTE: version = 1.0
LM-PARSER: ATTRIBUTE: xml:lang = en
LM-PARSER: Trying to close node: stream:stream
LM-PARSER: Have a new message
*** New message with type="stream:stream" from: jabber.ccc.de
*** XMPP 1.0 stream received: 2587321471

RECV [271]:
-----------------------------------
'<stream:features><starttls
xmlns='urn:ietf:params:xml:ns:xmpp-tls'/><mechanisms
xmlns='urn:ietf:params:xml:ns:xmpp-sasl'><mechanism>DIGEST-MD5</mechanism><mechanism>PLAIN</mechanism></mechanisms><register
xmlns='http://jabber.org/features/iq-register'/></stream:features>'
-----------------------------------
*** Read: 271 chars
LM-PARSER: ATTRIBUTE: xmlns = urn:ietf:params:xml:ns:xmpp-tls
LM-PARSER: Trying to close node: starttls
LM-PARSER: ATTRIBUTE: xmlns = urn:ietf:params:xml:ns:xmpp-sasl
LM-PARSER: Trying to close node: mechanism
LM-PARSER: Trying to close node: mechanism
LM-PARSER: Trying to close node: mechanisms
LM-PARSER: ATTRIBUTE: xmlns = http://jabber.org/features/iq-register
LM-PARSER: Trying to close node: register
LM-PARSER: Trying to close node: stream:features
LM-PARSER: Have a new message
*** New message with type="stream:features" from: unknown

SEND:
-----------------------------------
<starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls" id="936486936677"></starttls>

-----------------------------------
*** b_written: 80
*** wrote 80 bytes

RECV [50]:
-----------------------------------
'<proceed xmlns='urn:ietf:params:xml:ns:xmpp-tls'/>'
-----------------------------------
*** Read: 50 chars
LM-PARSER: ATTRIBUTE: xmlns = urn:ietf:params:xml:ns:xmpp-tls
LM-PARSER: Trying to close node: proceed
LM-PARSER: Have a new message
*** New message with type="proceed" from: unknown
*** Setting up SSL...
*** Hooray! SSL!
LM-SSL: lm-ssl-openssl.c: Cipher: TLSv1/SSLv3/AES256-SHA/256
LM-SSL: lm-ssl-openssl.c: SSL_get_verify_result() = 19
LM-SSL: lm-ssl-openssl.c: server = 'jabber.ccc.de', cn = 'jabber.ccc.de'
LM-SSL: lm-ssl-openssl.c:
    Issuer: /O=CAcert Inc./OU=http://www.CAcert.org/CN=CAcert Class 3 Root
    Subject: /C=DE/ST=Hamburg/L=Hamburg/O=Chaos Computer Club
e.V./CN=jabber.ccc.de
    For: jabber.ccc.de
Jul 27 13:29:17 Nokia-N900 telepathy-gabble[1719]: GLIB DEBUG gabble - do_auth:
authenticating with username: n900test, password: <hidden>, resource: Maemo
Jul 27 13:29:17 Nokia-N900 maemo-launcher[973]: child (pid=1722) terminated due
to exit()=0 
Jul 27 13:29:18 Nokia-N900 telepathy-gabble[1719]: GLIB DEBUG gabble -
connection_ssl_cb: called: An unknown SSL error occurred.
Jul 27 13:29:18 Nokia-N900 telepathy-gabble[1719]: GLIB MESSAGE default -
lm-ssl-openssl.c: Issued for CN: jabber.ccc.de
*** Could not begin SSL
*** SSL certificate verification failed
Freeing up IOChannel and file descriptor
Jul 27 13:29:18 Nokia-N900 telepathy-gabble[1719]: GLIB DEBUG gabble -
connection_disconnected_cb: called with reason 3

As you can see, the certificate for jabber.ccc.de is signed by CACert. I have
imported the CACert root certificates with the certificate manager and expected
the Jabber client to connect just fine.

However, it does not. Similar bugs might be bug 9262 or bug 8276.

I solved the problem by patching loudmouth so that it populates the
certificates in /home/user/.maemosec-certs/ssl-ca to OpenSSL.
loudmouth-1.4.1/loudmouth/lm-ssl-openssl.c around line 327 contains the calls
and the new version should o smth like

+    cert_path = g_build_filename (/*g_get_user_config_dir (),
+                                  "telepathy", "certs",
+                                  */
+                                  g_get_home_dir (),
+                                  ".maemosec-certs", "ssl-ca",


I am sorry to not provide a properly formatted patch but you can download the
patched sources here: 
https://muelli.cryptobitch.de/loudmouth_1.4.1-0osso10+0m6.tar.gz
Or a compiled version:
https://muelli.cryptobitch.de/libloudmouth1-0_1.4.1-0osso10+0m6_armel.deb