diff --git a/soapclient/SforceBaseClient.php b/soapclient/SforceBaseClient.php
index 4a59196..ed2ced6 100644
--- a/soapclient/SforceBaseClient.php
+++ b/soapclient/SforceBaseClient.php
@@ -566,6 +566,22 @@ protected function _sendEmail($arg) {
 	public function convertLead($leadConverts) {
 		$this->setHeaders("convertLead");
 		$arg = new stdClass();
+		foreach ($leadConverts as $k=>$lc) {
+		  if (isset($lc->contactRecord) && !$lc->contactRecord instanceof SoapVar) {
+			$lc->contactRecord = new SoapVar($lc->contactRecord, SOAP_ENC_OBJECT, 'Contact', $this->namespace);
+		  }
+
+		  if (isset($lc->opportunityRecord) && !$lc->opportunityRecord instanceof SoapVar) {
+			$lc->opportunityRecord = new SoapVar($lc->opportunityRecord, SOAP_ENC_OBJECT, 'Opportunity', $this->namespace);
+		  }
+
+		  if (isset($lc->accountRecord) && !$lc->accountRecord instanceof SoapVar) {
+			$lc->accountRecord = new SoapVar($lc->accountRecord, SOAP_ENC_OBJECT, 'Account', $this->namespace);
+		  }
+
+		  $leadConverts[$k] = $lc;
+		}
+		
 		$arg->leadConverts = $leadConverts;
 		return $this->sforce->convertLead($arg);
 	}