You can also configure two SLD's. One for SOLMAN and the other for the PI landscape and bridge them. Read the last part of this link to know the bridge.
http://wiki.scn.sap.com/wiki/display/SMSETUP/Connect+Managed+Systems+to+SLD
You may refer to the SLD planning guide.
http://scn.sap.com/docs/DOC-14151
Also here are some useful documents for SLD and LMDB.
http://scn.sap.com/docs/DOC-8042
http://scn.sap.com/docs/DOC-8817
Finally check these threads.
http://scn.sap.com/thread/3220352
Regards
RB