Index: typo3/sysext/rtehtmlarea/class.tx_rtehtmlarea_base.php
===================================================================
--- typo3/sysext/rtehtmlarea/class.tx_rtehtmlarea_base.php	(révision 8777)
+++ typo3/sysext/rtehtmlarea/class.tx_rtehtmlarea_base.php	(copie de travail)
@@ -380,7 +380,8 @@
 			}
 				// Register RTE windows
 			$this->TCEform->RTEwindows[] = $PA['itemFormElName'];
-			$textAreaId = htmlspecialchars(preg_replace('/\[|\]/', '_', $PA['itemFormElName']));
+			$textAreaId = preg_replace('/[^a-zA-Z0-9_:.-]/', '_', $PA['itemFormElName']);
+			$textAreaId = htmlspecialchars(preg_replace('/^[^a-zA-Z]/', 'x', $textAreaId));
 
 				// Check if wizard_rte called this for fullscreen edtition; if so, change the size of the RTE to fullscreen using JS
 			if (basename(PATH_thisScript) == 'wizard_rte.php') {
Index: typo3/sysext/rtehtmlarea/pi2/class.tx_rtehtmlarea_pi2.php
===================================================================
--- typo3/sysext/rtehtmlarea/pi2/class.tx_rtehtmlarea_pi2.php	(révision 8777)
+++ typo3/sysext/rtehtmlarea/pi2/class.tx_rtehtmlarea_pi2.php	(copie de travail)
@@ -248,7 +248,8 @@
 
 			// Register RTE windows:
 		$this->TCEform->RTEwindows[] = $PA['itemFormElName'];
-		$textAreaId = htmlspecialchars(preg_replace('/\[|\]/', '_', $PA['itemFormElName'])) . '_' . strval($this->TCEform->RTEcounter);
+		$textAreaId = preg_replace('/[^a-zA-Z0-9_:.-]/', '_', $PA['itemFormElName']);
+		$textAreaId = htmlspecialchars(preg_replace('/^[^a-zA-Z]/', 'x', $textAreaId)) . '_' . strval($this->TCEform->RTEcounter);
 
 			// Register RTE in JS:
 		$this->TCEform->additionalJS_post[] = $this->registerRTEinJS($this->TCEform->RTEcounter, '', '', '',$textAreaId);