Identical adjacent styles are not merged

[Tarto]

ENVIRONMENT
This was tested with the following browsers:
- Windows XP: Firefox2
- MacOS X: Safari3
And with FCKeditor 2.5 and 2.6

DESCRIPTION
1. Using any of the aforementioned browsers/OS, go to the demo page at http://www.fckeditor.net/demo
2. Apply an inline style such as "Marker: Yellow" to "This is so" at the beginning of the line
3. Apply the same style to "me sample text"
The generated source is:

<span style="background-color: Yellow;">This is so</span><span style="background-color: Yellow;">me <strong>sample text</strong></span>

But it would make more sense to merge the tags and output (as it is done in IE):

<span style="background-color: Yellow;">This is some <strong>sample text</strong></span>

This is obviously in the same category as ticket #2040, however I did not know if it can be considered as a duplicate and therefore created a new ticket.

[w.olchawa]

Confirmed using FCKeditor 2.6 and the current SVN in:

- Firefox 2.0.0.14 / Windows XP Professional

- Safari 3.1 / Windows XP Professional

IE doesn't seem to be affected.