Update:
I updated to 5.5.0b but looks like it didn't help. I still receive the same kind of errors and the same behavior.
inherited from com.vmware.vim.binding.vim.fault.InvalidLogin: Cannot complete login due to an incorrect user name or password.
Everything works from Windows client and Veeam but Web Client shows incorrect inventory information.
Also be warned, after updating to 5.5.0b my root and administrator@vsphere.local passwords were immediately expired. The only way I could log in and reset them was because I already had a ssh keypair for root set up.