diff --git a/ext/odbc/php_odbc.c b/ext/odbc/php_odbc.c
index eafa5483869..d54a46fb615 100644
--- a/ext/odbc/php_odbc.c
+++ b/ext/odbc/php_odbc.c
@@ -3122,6 +3122,10 @@ PHP_FUNCTION(odbc_columns)
 		schema = NULL;
 	}
 
+	if (cat && cat_len == 0) {
+		cat = NULL;
+	}
+
 	rc = SQLColumns(result->stmt, 
 			cat, (SQLSMALLINT) cat_len,
 			schema, (SQLSMALLINT) schema_len,
@@ -3184,6 +3188,10 @@ PHP_FUNCTION(odbc_columnprivileges)
 		efree(result);
 		RETURN_FALSE;
 	}
+	
+	if (cat_len == 0) {
+		cat = NULL;
+	}
 
 	rc = SQLColumnPrivileges(result->stmt, 
 			cat, SAFE_SQL_NTS(cat),
@@ -3260,6 +3268,10 @@ PHP_FUNCTION(odbc_foreignkeys)
 		efree(result);
 		RETURN_FALSE;
 	}
+	
+	if (pcat_len == 0) {
+		pcat = NULL;
+	}
 
 	rc = SQLForeignKeys(result->stmt, 
 			pcat, SAFE_SQL_NTS(pcat), 
@@ -3385,6 +3397,10 @@ PHP_FUNCTION(odbc_primarykeys)
 		efree(result);
 		RETURN_FALSE;
 	}
+	
+	if (cat_len == 0) {
+		cat = NULL;
+	}
 
 	rc = SQLPrimaryKeys(result->stmt, cat, SAFE_SQL_NTS(cat), schema, SAFE_SQL_NTS(schema), table, SAFE_SQL_NTS(table) );
 
@@ -3583,6 +3599,10 @@ PHP_FUNCTION(odbc_specialcolumns)
 		efree(result);
 		RETURN_FALSE;
 	}
+	
+	if (cat_len == 0) {
+		cat = NULL;
+	}
 
 	rc = SQLSpecialColumns(result->stmt, 
 			type,
@@ -3652,6 +3672,10 @@ PHP_FUNCTION(odbc_statistics)
 		efree(result);
 		RETURN_FALSE;
 	}
+	
+	if (cat_len == 0) {
+		cat = NULL;
+	}
 
 	rc = SQLStatistics(result->stmt, 
 			cat, SAFE_SQL_NTS(cat),
@@ -3715,6 +3739,10 @@ PHP_FUNCTION(odbc_tableprivileges)
 		efree(result);
 		RETURN_FALSE;
 	}
+	
+	if (cat_len == 0) {
+		cat = NULL;
+	}
 
 	rc = SQLTablePrivileges(result->stmt, 
 			cat, SAFE_SQL_NTS(cat),