This appears as an attempt to install the same architecture and version of a package that is already installed. This installation overwrites this package.
When upgrading a system with the "Entire Distribution plus OEM Cluster," the following packages seem to be added twice:
SUNWolinc
SUNWxwdim
SUNWxwinc
SUNWxwman
SUNWxwpmn
SUNWxwsrc
SUNWolbk
SUNWoldim
SUNWolman
SUNWolsrc
Workaround: If you try to add a package that has already been installed on a system, the installed package is overwritten.