Medieval Lands has him dying on 1106-07-21.
http://fmg.ac/Projects/MedLands/FRANCONIA%20(LOWER%20RHINE).htm#Ado...
In general, this whole line is all screwed up and needs to redone. My interpretation would be:
Adolf I-III - Adelheid von Laufen
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Adolf II-IV = Irmgarde von Schwarzensurg
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Eberhard I , etc.
After this has been settled, we can go back and consider the parents of Adolf I-III; of course, Medieval Lands end the line at Adolf I-III.