--- numbers.c.~1.193.~	2003-07-08 10:28:38.000000000 +1000
+++ numbers.c	2003-07-17 10:10:52.000000000 +1000
@@ -3947,7 +3947,7 @@
 {
   if (SCM_INUMP (z)) {
     if (SCM_INUM (z) >= 0) {
-      return scm_make_real (atan2 (0.0, 1.0));
+      return scm_flo0;
     } else {
       return scm_make_real (atan2 (0.0, -1.0));
     }
@@ -3957,10 +3957,13 @@
     if (sgn < 0) {
       return scm_make_real (atan2 (0.0, -1.0));
     } else {
-      return scm_make_real (atan2 (0.0, 1.0));
+      return scm_flo0;
     }
   } else if (SCM_REALP (z)) {
-    return scm_make_real (atan2 (0.0, SCM_REAL_VALUE (z)));
+    if (SCM_REAL_VALUE (z) >= 0)
+      return scm_flo0;
+    else
+      return scm_make_real (atan2 (0.0, -1.0));
   } else if (SCM_COMPLEXP (z)) {
     return scm_make_real (atan2 (SCM_COMPLEX_IMAG (z), SCM_COMPLEX_REAL (z)));
   } else {