diff --git a/etc/bashrc b/etc/bashrc
index 56d1663509..cd5e43239e 100644
--- a/etc/bashrc
+++ b/etc/bashrc
@@ -90,6 +90,22 @@ _foamSource()
 foamPrefs=`$WM_PROJECT_DIR/bin/foamEtcFile prefs.sh` && _foamSource $foamPrefs
 unset foamPrefs
 
+# Evaluate command-line parameters
+while [ $# -gt 0 ]
+do
+    case "$1" in
+    *=)
+        # name=       -> unset name
+        eval "unset ${1%=}"
+        ;;
+    *=*)
+        # name=value  -> export name=value
+        eval "export $1"
+        ;;
+    esac
+    shift
+done
+
 
 # Operating System/Platform
 # ~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/etc/cshrc b/etc/cshrc
index 77d2d6543c..95a594da6b 100644
--- a/etc/cshrc
+++ b/etc/cshrc
@@ -78,6 +78,21 @@ if ( $status == 0 ) then
 endif
 unset foamPrefs
 
+# Evaluate command-line parameters
+while ( $#argv > 0 )
+    switch ($argv[1])
+    case *=:
+        # name=       -> unsetenv name
+        eval "unsetenv $argv[1]:s/=//"
+        breaksw
+    case *=*:
+        # name=value  -> setenv name value
+        eval "setenv $argv[1]:s/=/ /"
+        breaksw
+    endsw
+    shift
+end
+
 
 # Operating System/Platform
 # ~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/etc/settings.csh b/etc/settings.csh
index 4bde0e7ee0..dc70c7fb48 100644
--- a/etc/settings.csh
+++ b/etc/settings.csh
@@ -121,7 +121,10 @@ case OpenFOAM:
         set gccDir=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER_ARCH/$gcc_version
         set gmpDir=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER_ARCH/$gmp_version
         set mpfrDir=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER_ARCH/$mpfr_version
-        set mpcDir=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER_ARCH/$mpc_version
+        if ( $?mpc_version ) then
+            set mpcDir=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER_ARCH/$mpc_version
+        endif
+
 
         # Check that the compiler directory can be found
         if ( ! -d "$gccDir" ) then