When logging in with mobile shell (mosh) sometimes in Ubuntu the locales will mismatch. This is easily fixed by using the following two commands:
# locale-gen "en_US.UTF-8"
# update-locale LC_ALL="en_US.UTF-8"
Substitute the locale for the one you wish to use in both places and then run this. For Swedish locale use sv_SE.UTF-8 as an example.