Steps to reproduce the issue

1. set "debug system" in global configuration to YES
2. provoke any kind of PHP error in a backend script (e.g. call an not existing function in
   /httpdocs/administrator/components/com_banners/banners.php )
3. call the "banners" component in the administration

Expected result

Give a general error message ("An error has occurred.") with as much information as possible.

Actual result

Gives a general error message ("An error has occurred.") and the PHP error message.
If "debug" is YES, you also get the "calling stack" shown.
What is (IMHO) missing is the actual script that is crashing and the codeline.

System information (as much as possible)

not really relevant i belief

Additional comments

script to deal with this: /httpdocs/administrator/templates/.../error.php

current code:
< ? php if ($this->debug) : ? >
< div >
< ? php echo $this->renderBacktrace(); ? >

I suggest to include the following code into
< ? php if ($this->debug) : ? >
< div >
< p >Scriptfile: < ? php echo htmlspecialchars($this->error->getFile(), ENT_QUOTES, 'UTF-8'); ? >< / p >
< p >Scriptline: < ? php echo htmlspecialchars($this->error->getLine(), ENT_QUOTES, 'UTF-8'); ?>< / p >
< / div >
< div >
< ? php echo $this->renderBacktrace(); ? >