diff --git a/nvm.sh b/nvm.sh
index 0e2a8a0..34d53dc 100644
--- a/nvm.sh
+++ b/nvm.sh
@@ -551,14 +551,10 @@ nvm() {
         nvm use $VERSION
         if ! nvm_has "npm" ; then
           echo "Installing npm..."
-          if [ "`expr "$VERSION" : '\(^v0\.1\.\)'`" != '' ]; then
+          if [[ $VERSION == v0.1.* || $VERSION == v0.2.[0-2] ]]; then
             echo "npm requires node v0.2.3 or higher" >&2
-          elif [ "`expr "$VERSION" : '\(^v0\.2\.\)'`" != '' ]; then
-            if [ "`expr "$VERSION" : '\(^v0\.2\.[0-2]$\)'`" != '' ]; then
-              echo "npm requires node v0.2.3 or higher" >&2
-            else
-              nvm_download https://npmjs.org/install.sh -o - | clean=yes npm_install=0.2.19 sh
-            fi
+          elif [[ $VERSION == v0.2.* ]]; then
+            nvm_download https://npmjs.org/install.sh -o - | clean=yes npm_install=0.2.19 sh
           else
             nvm_download https://npmjs.org/install.sh -o - | clean=yes sh
           fi