I am experiencing this as well - my workstation is running Win 7 Pro, Acrobat Pro XI. Laptop is running Win 7 Enterprise.
Created and and signed a document on the laptop - had to use Sign with Certificate in the Work with Certificates group.
There there are no I Need to Sign or Get Others Sign groups.
Opening the same signed PDF on my workstation, I have the I Need to Sign & Get Others to Sign groups, as well as the Work with Certificates group.
Another difference, when signing from my Win 7 Pro desktop, when I place signature, I need to provide my ID password. I do not have to do this when signing from the Win 7 Enterprise laptop.
The Acrobat Pro XI versions are both 11.0.06
