diff -up portaudio/portaudio-2.0.pc.in.alsa portaudio/portaudio-2.0.pc.in
--- portaudio/portaudio-2.0.pc.in.alsa	2011-05-05 11:55:28.000000000 +0200
+++ portaudio/portaudio-2.0.pc.in	2011-05-05 11:55:33.000000000 +0200
@@ -5,7 +5,7 @@ includedir=@includedir@
 
 Name: PortAudio
 Description: Portable audio I/O
-Requires:
+Requires: alsa
 Version: 19
 
 Libs: -L${libdir} -lportaudio @LIBS@