[FLOW3-general] enable bmp upload files

[Francesc Juliana]

Hello everybody:

I need to upload bmp files to a typo3 platform.
When I try to upload a bmp file an error appears:

File extension 'bmp' not allowed. (tt_content:309:image)

I have tried to update the
[imagefile_ext] adding bmp type.
If I check install again the [imagefile_ext]section is not changed. If I 
open localconf.php the new extension has been added..
But when I upload a bmp image the error appears again.
Anyone knows how can I solve this?

Thanks in advance.

Francesc