[horde] Horde Groupware Webmail Edition 1.2.7/1.2.8/1.2.9 with PHP4 shows blank page after login

[Nethub Online - Tommy]

To all,

I tested on version 1.2.7/1.2.8/1.2.9 /w PHP4 that have below problems:

=================================
Symptoms:
=================================
- If I set imp/config/servers.php to use POP3, after click login button
in the login page, it shows a blank page on the URL
xxx.com/horde/imp/redirect.php, and then I refresh the browser and click
"resend" button to submit again, then I can login the webmail,
NO ERROR IS SHOWN.

- If I set imp/config/servers.php to use IMAP, after click login button
in the login page, it shows a blank page on the URL
xxx.com/horde/imp/redirect.php, and then I refresh the browser and click
"resend" button to submit again, then I can login the webmail,
ERROR IS SHOWN AS BELOW:

[error in main frame]
Warning: reset() [function.reset]: Passed variable is not an array or 
object in 
/usr/local/apache/htdocs/horde-webmail-1.2.7/imp/lib/IMAP/Tree.php
 on line 249

Warning: Invalid argument supplied for foreach() in
/usr/local/apache/htdocs/horde-webmail-1.2.7/imp/lib/IMAP/Tree.php
 on line 496

Fatal error: Unsupported operand types in
/usr/local/apache/htdocs/horde-webmail-1.2.7/imp/lib/IMAP/Tree.php
 on line 333

[error in left frame]
Warning: reset() [function.reset]: Passed variable is not an array
 or object in
/usr/local/apache/htdocs/horde-webmail-1.2.7/imp/lib/IMAP/Tree.php
 on line 249

Warning: Invalid argument supplied for foreach() in
/usr/local/apache/htdocs/horde-webmail-1.2.7/imp/lib/IMAP/Tree.php
 on line 496

Fatal error: Unsupported operand types in
/usr/local/apache/htdocs/horde-webmail-1.2.7/imp/lib/IMAP/Tree.php
 on line 333


=================================
Environments:
=================================
- Problem occurs on Horde Groupware Webmail Edition 1.2.7/1.2.8/1.2.9
 with PHP4.4.9

- No problem on Horde Groupware Webmail Edition 1.2.7/1.2.8/1.2.9
 with PHP5.2.14

- No problem on Horde Groupware Webmail Edition 1.2.6 with PHP4.4.9

- No problem on Horde Groupware Webmail Edition 1.2.6 with PHP5.2.14

- testing server is CentOS 4.5, Apache 2.2.6, MySQL 4.0.27


=================================
More information:
=================================
- If I go to URL xxx.com/horde/test.php, it is blank page as well,
after I deleted the line 
"$pear_output = $horde_test->PEARModuleCheck($pear_list);"
then it can show up the testing info.

- No problem to run xxx.com/horde/imp/test.php: 
PEAR: Yes, Recent PEAR: Yes, Auth_SASL: Yes, HTTP_Request: Yes

- did execute "(4) Update PEAR for a new or changed location"

- no error log or login log in /tmp/horde.log, 
only has Logout log in /tmp/horde.log



Although PHP4.4.9 is very old version, but Horde requires PHP4.3+ so 
I think this problem should not be resolved by upgrading PHP version.

Thank you for any assistance you can provide.
Please let me know if further information is needed.