You need MesInput app from store http://store.ovi.com/content/161100 and there is few additional layoust, Serbian (cyr and latin) Bosnian, Croatian, Slovenian as well.
Also with few tweak is possible to run Sebian dictionary in swype.
Steps:
1. Download SerbianLA.zdb.le
2. Rename it to a dictionary that you are willing to sacrifice (in my case Dansk.zdb.le)
3.Copy it to /home/user/.swype/data and replace the old file or delete the old one first,.
4. Use swype serbian dict as Dansk
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