diff --git a/Shorewall/Perl/Shorewall/Config.pm b/Shorewall/Perl/Shorewall/Config.pm
index 2f953d77f..fc8e3dc10 100644
--- a/Shorewall/Perl/Shorewall/Config.pm
+++ b/Shorewall/Perl/Shorewall/Config.pm
@@ -1858,16 +1858,19 @@ sub read_a_line(;$) {
 
 	    my $count = 0;
 	    #
-	    # Expand Shell Variables using %params
+	    # Expand Shell Variables using %params and %ENV
 	    #
 	    #                            $1      $2      $3           -     $4
 	    while ( $currentline =~ m( ^(.*?) \$({)? ([a-zA-Z]\w*) (?(2)}) (.*)$ )x ) {
+
+		unless ( exists $params{$3} ) {
+		    $params{$3} = $ENV{$3} if exists $ENV{$3};
+		}
+
 		my $val = $params{$3};
-		
-		$params{$3} = $ENV{$3} if exists $ENV{$3};
 
 		unless ( defined $val ) {
-		    fatal_error "Undefined shell variable (\$$3)" unless exists $params{$3};
+		    fatal_error "Undefined shell variable (\$$3)" unless exists $params{$3} || exists $ENV{$3};
 		    $val = '';
 		}
 
@@ -2882,9 +2885,8 @@ sub unsupported_yes_no_warning( $ ) {
 # Process the params file
 #
 sub get_params() {
-    my $fn = find_file 'params';
+    if ( my $fn = find_file 'params' ) {
 
-    if ( $fn ) {
 	progress_message2 "Processing $fn ...";
 
 	my @params = `$globals{SHAREDIRPL}/getparams $fn`;
diff --git a/Shorewall/Perl/getparams b/Shorewall/Perl/getparams
index d719f92e9..36d237082 100755
--- a/Shorewall/Perl/getparams
+++ b/Shorewall/Perl/getparams
@@ -24,7 +24,7 @@
 exported=$(env | sed 's/=.*//');
 
 #
-# Sigh -- POSIX shells don't support 'typeset' or 'declare'
+# Sigh -- POSIX shells don't support 'typeset +x' or 'declare +x'
 #
 
 for v in $exported; do
diff --git a/Shorewall/releasenotes.txt b/Shorewall/releasenotes.txt
index 88291f89b..dd3b0c6ed 100644
--- a/Shorewall/releasenotes.txt
+++ b/Shorewall/releasenotes.txt
@@ -30,13 +30,14 @@ VI.   PROBLEMS CORRECTED AND NEW FEATURES IN PRIOR RELEASES
 
 1)  Previously, /usr/share/shorewall/compiler.pl expected the contents
     of the params file to be passed in the environment. Now, the
-    compiler invokes the shell program /usr/share/shorewall/getparams
-    to process the file and to pass the (variable,value) pairs back to
-    the compiler.
+    compiler invokes a small shell program
+    (/usr/share/shorewall/getparams) to process the file and to pass
+    the (variable,value) pairs back to the compiler.
 
-    In this new implementation, the contents of the environment of the
-    program that launches /usr/share/shorewall/compiler.pl overrides
-    the contents of /etc/shorewall/params.
+    Shell variable expansion uses the value from the params file if the
+    parameter was set in that file. Otherwise the current environment
+    is used. If the variable does not appear in either place, an error
+    message is generated.
 
 ----------------------------------------------------------------------------
              I V.  R E L E A S E  4 . 4  H I G H L I G H T S