Problem with é and ' characters using us intl keyboard on the server

The problem is reproducible on both of my clients. One use XP and the other windows 7.

I'm using Ubuntu 14.04.1 LTS with synergy 1.4.12-3ubuntu1

The é and ' (single quote) are typing two keys.

{e + '} = é
{ '+ space}= '

It worked before as expected, but now this is what is happening:

{e+'} = e
{'+space}= space

The other accents are working fine, it is just the acute which is not recognized. The problem is reproducible for all vowels when combined to the acute accent.