Magento Compare Version

Data.php

<?php
class Myvendor_Mymodule_Helper_Data extends Mage_Core_Helper_Data
{
    /**
     * Check whether current Magento version supports Transactions
     */
    public function isTransactionSupported()
    {
        return version_compare(Mage::getVersion(), '1.4.0.1', '>');
    }
}