Some clarifications are needed:
There is no support team not even "them" or "they".
1. This is open source development,
2. Not a commercial company, there is no charging for any licences, support fees,
3. This GPL program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
I am alone maintaining 18 extensions, and I develop for a living in java, 60hours per week are common, php is done when i have time.
and yes: you'll have to go to 2.5, Joomla 1.5 is end of life
Joomla 1.5 is what the Joomla team refer to as an LTS or Long Term Support Release. It was released in January of 2008 and has seen only minor bug fixes and security releases in nearly 4 years. The current version is 1.5.25 and support for this LTS version is set to end in April 2012. If you have not already done so, you should be strongly thinking about moving to Joomla 2.5 in the near future to ensure that you are running on the most stable, secure, and best supported Joomla platform.
I will correct in version 1.5 only security issues but wont make any per user improvements, this code is used in Joomla 1.5 and nobody complains.