Added the trim() function to the URL that is used as the update
source. A forgotten small whitespace after the URL in the XML file may
throw a confusing error message.
Bugtracker #28333: JFTP call "DL" function that sometimes is removed by hosting environment and cause fatal error without message 

The fix is present in Joomla 2.5 and not present in 3.1

The reason of the issue is due to the fact that the "dl" function is called event when FTP layer is not used.
As soon as a jimport load the FTP client somewhere it cause a fatal error that is hide due to the "@dl" that does not report error.

The fix consists in checking that function "dl" exists before calling it.

To reproduce it, you need to setup a server that does not contain the FTP module and that does not include the "dl" function.
Becarefull that most WAMP or similar include the FTP and dl in the core that can not be removed.
 $ [#31290] Add Debug User Group Help Screen language string. Thanks
George Wilson
(Fix #1386)
 # [#31348] Regression for plugin filter search with spaces in the
title. Reverting
 # [#27935] 'Next' button not working on first try after login in
com_users. Thanks Antonio Durán Terrés and Brian Teeman (Fix #938)
# [#31477] Remove unneeded GROUP BY and fix duplicate article display.
Thanks Thomas Hunziker
(Fix #1545)
 # Performance bug - Initial patch partially reverted  2.5 Fix
(Regression) Thanks Thomas Hunziker
(Fix #1554)
[#31319] registration option disabled by default is safer. Thanks Brian
Teeman.
Prepare for 2.5.12 release
Prepare for 2.5.13 release
Fix version date.
Fix build program using new zip. Thanks Roberto Segura.
Revert "Fix build program using new zip. Thanks Roberto Segura."

This reverts commit f950d2cacbb8e831446bb45c1ba22091c4efeeb2.
Prepare for 2.5.14 development
Add ability to place named variables in language strings [J2.5]

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=31587

This is the Joomla 2.5 PR of #880 & #1597
 # Missing list of Subcategories in a blog view. Revert [#30150]
Prepare 2.5.14 release
Reset for development
oops
 # [#31411] Show Offline image only if it exists. Thanks Tobias Zulauf
(Fix #1454)