diff --git a/mozilla/xpcom/base/nsIVersionComparator.idl b/mozilla/xpcom/base/nsIVersionComparator.idl
index fa0f6952a22..1ada0ef17b3 100755
--- a/mozilla/xpcom/base/nsIVersionComparator.idl
+++ b/mozilla/xpcom/base/nsIVersionComparator.idl
@@ -45,6 +45,9 @@
  *
  * <number-a><string-b><number-c><string-d (everything else)>
  *
+ * A version-part may also consist of a single asterisk "*" which indicates
+ * "infinity".
+ *
  * Numbers are base-10, and are zero if left out.
  * Strings are compared bytewise.
  *
diff --git a/mozilla/xpcom/glue/nsVersionComparator.cpp b/mozilla/xpcom/glue/nsVersionComparator.cpp
index 81429ec0dab..2ceb68c6966 100755
--- a/mozilla/xpcom/glue/nsVersionComparator.cpp
+++ b/mozilla/xpcom/glue/nsVersionComparator.cpp
@@ -74,7 +74,13 @@ ParseVP(char *part, VersionPart &result)
   if (dot)
     *dot = '\0';
 
-  result.numA = strtol(part, NS_CONST_CAST(char**, &result.strB), 10);
+  if (part[0] == '*' && part[1] == '\0') {
+    result.numA = PR_INT32_MAX;
+    result.strB = "";
+  }
+  else {
+    result.numA = strtol(part, NS_CONST_CAST(char**, &result.strB), 10);
+  }
 
   if (!*result.strB) {
     result.strB = nsnull;
diff --git a/mozilla/xpcom/tests/TestVersionComparatorRunner.pl b/mozilla/xpcom/tests/TestVersionComparatorRunner.pl
index 0e8f012e905..54cbb8770c4 100755
--- a/mozilla/xpcom/tests/TestVersionComparatorRunner.pl
+++ b/mozilla/xpcom/tests/TestVersionComparatorRunner.pl
@@ -52,6 +52,8 @@ my $executable = shift;
   "1.1",
   "1.1.0.1",
   "1.1.1",
+  "1.1.*",
+  "1.*",
   "2.0",
   "2.1",
   "3.0.-1",