query string dash special character

Hello.
Im trying to pass a value using querystring so when i click on a link its value gets selected in a new page drop down list. I got it working but when i add a dash character to the value it stops working.
I tried changing to url friendly character like & ndash ; also but that didnt help neither.
Any ideas what i can do to make it work?

Thanks for your help.
I tried to use dash with no spaces like you and it worked. But is it possible to make it work with blank spaces like: "Second - Choice"?
(It works with one space in either side aswell but not with two.)

Thanks for your reply.
I tried to replace (also urlencode, str_replace, etc), but no luck. Here you can see the example, when you click "Intresseanmälan" at this page:
http://www.vialatina.se/?resepaket=colombia-varldsarvsstaden-cartagena

You get to a gravity form where the drop down "Resepaket" should be dynamically filled.
Worth mentioning is that i also tried changing the populate_dropdown function in wordpress.

If i change it to "resepaket" it ADDS the value to the dropdown. I just want to MATCH the value so it gets selected. (that dropdown is dynamically populated with the parameter name "resepaketet")

I can copy everything and put in another server and give you access, BUT before i go thru all that hussle, i found out something that might be of help.

When i quickedit the post and update without even changing anything, it works like it should!

When i update the post from regular edit screen (and rewrite the dash again in the title) it stops working.

Maybe with this info you know a fix for this that doesnt involve quickedit/update every post?
Let me know if you still want me to copy everything to another server and give you access.