OT: are chars above ascii 126 allowed in system passwords?

[Tiemo Hollmann TB]

Hello,

I have not much knowledge in server administration. My LiveCode program
establishes a http connection. In case there is a network proxy server, the
user can enter the proxy server credentials in my program to get access to
the internet. That works ok so far, but my password field can’t handle
German Umlaute äüö and ß (rawKeyCodes 223 and above). From time to time I
get a customer feedback that they can’t get thru the proxy even after having
entered the credentials in my program. Since they were not sure about their
network topography and didn’t wanted to tell me their pw, I still don’t
know, if it didn’t worked because they had perhaps Umlaute in their pw or
because of any other (network) reason. Before I start fiddling around to get
these characters as valid chars I wanted to ask, if somebody knows, if these
characters are allowed in system passwords (of proxy servers, etc.) at all.
If not I can just go on without these special characters and search for
other issues.

Thanks for any experience

Tiemo