Thanks for the report. I am no longer able to support this plugin. Patches welcome :-)

Needing the same feature.
Many people do actually 8O when reading and searching this forum.

Anyway, the plugin you mentioned doesn't seems to work (very well) in Mantis 2.x :(

But I do got it to work with a few workarounds :)

STEP 1) change the following lines in file 'LinkedCustomFields.php':

$this->version = "1.0.1";

$this->requires = array(

"MantisCore" => "1.2.6, <2.30.0",

"jQuery" => "1.8"

);

$this->requires = array(
"MantisCore" => "1.2.6, <2.30.0",

STEP 2) Install the plugin

STEP 3) Change de database table 'plugin_linkedcustomfields_data' by your self.

DONE.

But I don't prefer this workaround.
Alternative solution might be a custom field which is only visible when a particular category is selected?

If anyone has a better solution???
Please let me know!
Thanks in advanced.

There is an update! See issue 0024226

@Marinix, I have tried you solution and It's does not work. Did you find any other ways ?
Thank you

I have just updated the plugin, which should now support MantisBT 2.3 or later.
https://github.com/mantisbt-plugins/LinkedCustomFields

Note that this there is no official release just yet, testing and feedback would be appreciated (please create issues at GitHub or ping me on Gitter).