I had a similar problem, after a bit of googling I found it was a bug.
The messy fix for it is to wipe the history of what packages are installed and then use -nodeps flag with ipkg for installing webif.
rm /usr/lib/ipkg/status
ipkg install -nodeps webif_0.3-10_mips.ipk
You'll need to use the -nodeps for some other packages too, there is probably a better way to fix it .
I'm not really a linux person.
Buts it quick and works , for me anyways.