malformed Icon key 'skype.png'

I'm seeing this periodically in my syslog, the entire warning is:

EggSMClient-WARNING: Desktop file
'/home/chris/.config/gnome-session/saved-session/109c663caf2a36eb79130670966442063800000010000090.desktop' has malformed Icon key 'skype.png'(should not include extension)

Any ideas on what's causing this or how to prevent it.

-- 
Chris
KeyID 0xE372A7DA98E6705C
31.11°N 97.89°W (Elev. 1092 ft)
07:50:14 up 121 days, 13:29, 1 user, load average: 0.15, 0.18, 0.22

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