--- a/configure.in
+++ b/configure.in
@@ -62,7 +62,7 @@
      ;;
   *)
      AC_MSG_RESULT($withval)
-     if test -f $withval/include/event.h -a -f $withval/lib/libevent.a; then
+     if test -f $withval/include/event.h -a -f $withval/lib/libevent.so; then
         owd=`pwd`
         if cd $withval; then withval=`pwd`; cd $owd; fi
         EVENTINC="-I$withval/include"