[TYPO3-english] mail sending configuration problem

[Gábor Horn]

Hello,

i have a webserver which hosts many Typo3 sites with different versions, 
and with a recently migrated site i have problems with mails. The details:

1, this is a Typo3 4.4.7 system with quite complex configuration and 
some custom plugins so not very easy just to migrate the newest, and i 
don't think it's the Typo3 version that is the problem, i think it might 
be some configuration which still refers somehow to the previous 
server/environment the site was running on
2, sending testmail from install tool silently fails, no error but mail 
never arrives
3, from the same server a fresh installation of Typo3 4.5.5 just sends 
emails nicely from the install tool (and extensions), and did also 
before update and it was 4.3.3, and all other and differnet versions of 
Typo3 installations on the server sends emails fine, so i think it's not 
a server configuration issue
4, within this very problematic site sending emails with Direct Mail's 
mailtest (as well as its cronjob) works just fine
5, but other extensions like sr_feuser_register cannot send email. Also 
experience a noticable delay when registering a user on the frontend 
with sr_feuser_register at the final step after confirming my details 
and before getting the confirmation page about "we've sent you an email 
please click on the link in it to activate your registration" message. 
Some 20-30 secs of waiting here, as if something would timeout in the 
background. Althought when i try send email from installtool (both with 
Test t3lib_htmlmail checker or not) i don't experience such delay, only 
the fact the mail never arrives. No spam filtering issue, i think that 
might affect all other Typo3 install tool test mails as well.

In the localconf.php the following TYPO3['SYS'] values are set/changed:

$TYPO3_CONF_VARS['SYS']['sitename']
$TYPO3_CONF_VARS['SYS']['sitename']
$TYPO3_CONF_VARS['SYS']['encryptionKey']
$TYPO3_CONF_VARS["SYS"]["forceReturnPath"]
$TYPO3_CONF_VARS["SYS"]["no_pconnect"]
$TYPO3_CONF_VARS["SYS"]["t3lib_cs_convMethod"]
$TYPO3_CONF_VARS["SYS"]["t3lib_cs_utils"]
$TYPO3_CONF_VARS['SYS']['setDBinit']
$TYPO3_CONF_VARS['SYS']['enable_DLOG']
$TYPO3_CONF_VARS['SYS']['devIPmask']
$TYPO3_CONF_VARS['SYS']['displayErrors']
$TYPO3_CONF_VARS['SYS']['curlUse']
$TYPO3_CONF_VARS['SYS']['sqlDebug']
$TYPO3_CONF_VARS['SYS']['forceReturnPath']
$TYPO3_CONF_VARS['SYS']['textfile_ext']
$TYPO3_CONF_VARS['SYS']['recursiveDomainSearch']
$TYPO3_CONF_VARS['SYS']['compat_version']
$TYPO3_CONF_VARS['SYS']['systemLogLevel']
$TYPO3_CONF_VARS['SYS']['cookieHttpOnly']
$TYPO3_CONF_VARS['SYS']['useCachingFramework']
$TYPO3_CONF_VARS['SYS']['enable_errorDLOG']
$TYPO3_CONF_VARS['SYS']['enable_exceptionDLOG']
$TYPO3_CONF_VARS['SYS']['enableDeprecationLog']
$TYPO3_CONF_VARS['SYS']['phpTimeZone']
$TYPO3_CONF_VARS['SYS']['exceptionalErrors']
$TYPO3_CONF_VARS['SYS']['systemLog']

anybody please have an idea if any of those might affect the mail 
sending? Or any $TYPO3_CONF_VARS['BE'] or $TYPO3_CONF_VARS['EXT'] might 
couse the problem? I thought the install tool doesn't use those.

I also have a setting for 
$TYPO3_CONF_VARS['EXT']['extConf']['stoefln_pear_mail'] which is 
supposed to XClass t3lib_hmtlmail for usign pear to send mails - 
althought uncommenting it doesnt affect neither install tool test mail 
(still doesn't work) nor diect mail (still works).

Anybody please have an idea how i could debug this issue?

thanks, Gabor Horn