diff --git a/cpr.c b/cpr.c
index d641670..3f8187b 100644
--- a/cpr.c
+++ b/cpr.c
@@ -250,8 +250,26 @@ int decodeCPRsurface(double reflat, double reflon,
     //      reflat=-40, rlat=4, use rlat=4
     //      reflat=-40, rlat=6, use rlat=6-90 = -84
 
-    if ( (rlat0 - reflat) > 45 ) rlat0 -= 90;
-    if ( (rlat1 - reflat) > 45 ) rlat1 -= 90;
+    // As a special case, -90, 0 and +90 all encode to zero, so
+    // there's a little extra work to do there.
+
+    if (rlat0 == 0) {
+        if (reflat < -45)
+            rlat0 = -90;
+        else if (reflat > 45)
+            rlat0 = 90;
+    } else if ((rlat0 - reflat) > 45) {
+        rlat0 -= 90;
+    }
+
+    if (rlat1 == 0) {
+        if (reflat < -45)
+            rlat1 = -90;
+        else if (reflat > 45)
+            rlat1 = 90;
+    } else if ((rlat1 - reflat) > 45) {
+        rlat1 -= 90;
+    }
 
     // Check to see that the latitude is in range: -90 .. +90
     if (rlat0 < -90 || rlat0 > 90 || rlat1 < -90 || rlat1 > 90)
diff --git a/cprtests.c b/cprtests.c
index 182aa19..751ba80 100644
--- a/cprtests.c
+++ b/cprtests.c
@@ -73,6 +73,13 @@ static const struct {
     {   7.00,   0.00, 105730, 9259, 29693, 8997, 0, 52.209984 - 90.0, 0.135269,  0, 52.209976 - 90.0, 0.134299 },
     { -52.00,   0.00, 105730, 9259, 29693, 8997, 0, 52.209984 - 90.0, 0.135269,  0, 52.209976 - 90.0, 0.134299 },
     { -90.00,   0.00, 105730, 9259, 29693, 8997, 0, 52.209984 - 90.0, 0.135269,  0, 52.209976 - 90.0, 0.134299 },
+
+    // poles/equator cases
+    { -46.00, -180.00,  0, 0,  0, 0,  0, -90.0, -180.000000,  0, -90.0, -180.0 },   // south pole
+    { -44.00, -180.00,  0, 0,  0, 0,  0,   0.0, -180.000000,  0,   0.0, -180.0 },   // equator
+    {  44.00, -180.00,  0, 0,  0, 0,  0,   0.0, -180.000000,  0,   0.0, -180.0 },   // equator
+    {  46.00, -180.00,  0, 0,  0, 0,  0,  90.0, -180.000000,  0,  90.0, -180.0 },   // north pole
+
 };
 
 // Relative CPR test data:
@@ -138,7 +145,6 @@ static const struct {
     { 52.00,    1.40,  29693, 8997, 1, 1, 0, 52.209976, 0.176507 },   // odd, surface
     { 52.00,   -1.05, 105730, 9259, 0, 1, 0, 52.209984, 0.176601 },   // even, surface
     { 52.00,   -1.05,  29693, 8997, 1, 1, 0, 52.209976, 0.176507 },   // odd, surface
-
 };
 
 static int testCPRGlobalAirborne() {
@@ -215,7 +221,7 @@ static int testCPRGlobalSurface() {
             || fabs(rlon - cprGlobalSurfaceTests[i].even_rlon) > 1e-6) {
             ok = 0;
             fprintf(stderr,
-                    "testCPRGlobalSurface[%d]:  FAIL: decodeCPRsurface(%.6f,%.6f,%d,%d,%d,%d,EVEN) failed:\n"
+                    "testCPRGlobalSurface[%d,EVEN]:  FAIL: decodeCPRsurface(%.6f,%.6f,%d,%d,%d,%d,EVEN) failed:\n"
                     " result %d  (expected %d)\n"
                     " lat %.6f   (expected %.6f)\n"
                     " lon %.6f   (expected %.6f)\n",
diff --git a/debian/dump1090-mutability.postinst b/debian/dump1090-mutability.postinst
index ae7935e..d24781f 100644
--- a/debian/dump1090-mutability.postinst
+++ b/debian/dump1090-mutability.postinst
@@ -126,7 +126,7 @@ case "$1" in
         if [ -e /etc/lighttpd/conf-enabled/89-dump1090.conf ]; then
             if dpkg --compare-versions "$2" le "1.14"; then
                 echo "Restarting lighttpd.." >&2
-                service lighttpd restart || echo "Warning: lighttpd failed to restart." >&2
+                invoke-rc.d lighttpd restart || echo "Warning: lighttpd failed to restart." >&2
             fi
         fi
     ;;