diff --git a/install/scripts/install_ocaml.sh b/install/scripts/install_ocaml.sh
index 5718ed3..78e1ef9 100755
--- a/install/scripts/install_ocaml.sh
+++ b/install/scripts/install_ocaml.sh
@@ -7,8 +7,44 @@ cd .. ; QMCCHEM_PATH="$PWD" ; cd -
 PACKAGES="core cryptokit ocamlfind sexplib" # ppx_sexp_conv"
 
 declare -i i
-i=$(gcc -dumpversion | cut -d '.' -f 2)
-if [[ i -lt 6 ]]
+
+# return 0 if program version is equal or greater than check version
+check_version () {
+    if [[ $1 == $2 ]]
+    then
+        return 0
+    fi
+    local IFS=.
+    local i ver1=($1) ver2=($2)
+    # fill empty fields in ver1 with zeros
+    for ((i=${#ver1[@]}; i<${#ver2[@]}; i++))
+    do
+        ver1[i]=0
+    done
+    for ((i=0; i<${#ver1[@]}; i++))
+    do
+        if [[ -z ${ver2[i]} ]]
+        then
+            # fill empty fields in ver2 with zeros
+            ver2[i]=0
+        fi
+        if ((10#${ver1[i]} > 10#${ver2[i]}))
+        then
+            return 1
+        fi
+        if ((10#${ver1[i]} < 10#${ver2[i]}))
+        then
+            return 2
+        fi
+    done
+    return 0
+}
+
+
+i=$(gcc -dumpversion)
+
+check_version 4.6 $i
+if [[ $? == 1 ]]
 then
    echo "GCC version $(gcc -dumpversion) too old. GCC >= 4.6 required."
    exit 1