As a user already posted here:
http://forums.opensuse.org/english/get-technical-help-here/applications/465428-dolphin-konqueror-problem-sftp.html

if I use dolphin to connect to my server using sftp it doesn't connect:
if in a terminal I do ssh user@mysite.noip.org it ask me password and is ok
if in a terminal I do sftp user@mysite.noip.org it ask me password and is ok
if in dolphin I use fish://mysite.noip.org/ dolphin ask me user and password and is ok
if in dolphin I use sftp://mysite.noip.org/ dolphin ask me user and password and it say the user or password are wrong

Reproducible: Always

Steps to Reproduce:
1. create a resource button in dolphin to connect to your server
2. put in address sftp://mysite.noip.org/   or    sftp://user@mysite.noip.org/
3. try to use the button to connect to the sftp service of the server
Actual Results:  
user / password not valid

Expected Results:  
I expect to connect to the server

Fedora 17 KDE (it happens even on 16 versione and on other distros too)
KDE 4.8.4