diff --git a/interface/lib/classes/tform.inc.php b/interface/lib/classes/tform.inc.php
index 308c6c0b58a719421c107593092e85ab91d38a08..d2d0e5db6a395dd2f66daad453d210484f3a077a 100644
--- a/interface/lib/classes/tform.inc.php
+++ b/interface/lib/classes/tform.inc.php
@@ -630,6 +630,16 @@ class tform {
 											 $this->errorMessage .= $errmsg."<br />\r\n";
 										  }
                                         }
+                                break;
+								case 'ISIPV4':
+                                        if(!preg_match("/^[0-9]{1,3}(.)[0-9]{1,3}(.)[0-9]{1,3}(.)[0-9]{1,3}$/", $field_value)) {
+                                                $errmsg = $validator['errmsg'];
+                                                if(isset($this->wordbook[$errmsg])) {
+                                                    $this->errorMessage .= $this->wordbook[$errmsg]."<br />\r\n";
+												} else {
+													$this->errorMessage .= $errmsg."<br />\r\n";
+												}
+                                        }
                                 break;
                                 case 'CUSTOM':
                                         // Calls a custom class to validate this record