ERROR_INVALID_PIN in gschem


I am attaching a netnames and when I netlist, I get a whole
bunch of ERROR_INVALID_PIN errors. Can someone tell me what is
going wrong ?
Thanks
-Rahul


* Spice netlist
V3 Vin 0 pulse 0 35 0u 25n 25n 25u 500u
V2 O2 0 pulse 0 35 25u 25n 25n 25u 50u
V1 O1 0 pulse 0 35 0n 25n 25n 25u 50u
C4 0 b4 270e-12
C3 0 b3 270e-12
C2 0 b2 270e-12
C1 0 b1 270e-12
M15 O1 12 b2 ERROR_INVALID_PIN ERROR_INVALID_PIN ERROR_INVALID_PIN tft0 l=9e-6 w=4.8e-3
M16 b2 O2 0 ERROR_INVALID_PIN ERROR_INVALID_PIN ERROR_INVALID_PIN tft0 l=9e-6 w=2.4e-3
M13 O2 O2 12 ERROR_INVALID_PIN ERROR_INVALID_PIN ERROR_INVALID_PIN tft0 l=9e-6 w=300e-6
M14 12 9 0 ERROR_INVALID_PIN ERROR_INVALID_PIN ERROR_INVALID_PIN tft0 l=9e-6 w=1.2e-3
M11 O2 11 b1 ERROR_INVALID_PIN ERROR_INVALID_PIN ERROR_INVALID_PIN tft0 l=9e-6 w=4.8e-3

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