Empathy

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License: gpl, lgpl21

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Licq   (Compare Project)

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Digsby   (Compare Project)

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Pidgin IM (ex-Gaim)   (Compare Project)

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ayttm   (Compare Project)

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Ubiety   (Compare Project)

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License: lgpl3

emesene   (Compare Project)

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OneTeam Desktop   (Compare Project)

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License: gpl, mozilla_public_1_1