diff --git a/src/ls_odbc.c b/src/ls_odbc.c
index 494dedb..9fe1a84 100644
--- a/src/ls_odbc.c
+++ b/src/ls_odbc.c
@@ -119,7 +119,7 @@ static int fail(lua_State *L,  const SQLSMALLINT type, const SQLHANDLE handle) {
     SQLINTEGER NativeError;
     SQLSMALLINT MsgSize, i;
     SQLRETURN ret;
-    char Msg[SQL_MAX_MESSAGE_LENGTH];
+    SQLCHAR Msg[SQL_MAX_MESSAGE_LENGTH];
     luaL_Buffer b;
     lua_pushnil(L);
 
@@ -129,7 +129,7 @@ static int fail(lua_State *L,  const SQLSMALLINT type, const SQLHANDLE handle) {
         ret = SQLGetDiagRec(type, handle, i, State, &NativeError, Msg, 
                 sizeof(Msg), &MsgSize);
         if (ret == SQL_NO_DATA) break;
-        luaL_addlstring(&b, Msg, MsgSize);
+        luaL_addlstring(&b, (char*)Msg, MsgSize);
         luaL_addchar(&b, '\n');
         i++;
     } 
@@ -363,7 +363,7 @@ static int cur_coltypes (lua_State *L) {
 /*
 ** Creates two tables with the names and the types of the columns.
 */
-static void create_colinfo (lua_State *L, cur_data *cur) {
+static int create_colinfo (lua_State *L, cur_data *cur) {
 	SQLCHAR buffer[256];
 	SQLSMALLINT namelen, datatype, i;
 	SQLRETURN ret;
@@ -375,15 +375,21 @@ static void create_colinfo (lua_State *L, cur_data *cur) {
 	names = lua_gettop (L);
 	for (i = 1; i <= cur->numcols; i++) {
 		ret = SQLDescribeCol(cur->hstmt, i, buffer, sizeof(buffer), 
-                &namelen, &datatype, NULL, NULL, NULL);
-		/*if (ret == SQL_ERROR) return fail(L, hSTMT, cur->hstmt);*/
-		lua_pushstring (L, buffer);
+			&namelen, &datatype, NULL, NULL, NULL);
+		if (ret == SQL_ERROR) {
+			lua_pop(L, 2);
+			return -1;
+		}
+
+		lua_pushstring (L, (char*)buffer);
 		lua_rawseti (L, names, i);
 		lua_pushstring(L, sqltypetolua(datatype));
 		lua_rawseti (L, types, i);
 	}
 	cur->colnames = luaL_ref (L, LUA_REGISTRYINDEX);
 	cur->coltypes = luaL_ref (L, LUA_REGISTRYINDEX);
+
+	return 0;
 }
 
 
@@ -391,25 +397,30 @@ static void create_colinfo (lua_State *L, cur_data *cur) {
 ** Creates a cursor table and leave it on the top of the stack.
 */
 static int create_cursor (lua_State *L, int o, conn_data *conn, 
-        const SQLHSTMT hstmt, const SQLSMALLINT numcols) {
-    cur_data *cur = (cur_data *) lua_newuserdata(L, sizeof(cur_data));
+	const SQLHSTMT hstmt, const SQLSMALLINT numcols)
+{
+	cur_data *cur = (cur_data *) lua_newuserdata(L, sizeof(cur_data));
 	luasql_setmeta (L, LUASQL_CURSOR_ODBC);
 
 	conn->cur_counter++;
-    /* fill in structure */
+
+	/* fill in structure */
 	cur->closed = 0;
 	cur->conn = LUA_NOREF;
-    cur->numcols = numcols;
+	cur->numcols = numcols;
 	cur->colnames = LUA_NOREF;
 	cur->coltypes = LUA_NOREF;
-    cur->hstmt = hstmt;
+	cur->hstmt = hstmt;
 	lua_pushvalue (L, o);
-    cur->conn = luaL_ref (L, LUA_REGISTRYINDEX);
+	cur->conn = luaL_ref (L, LUA_REGISTRYINDEX);
 
 	/* make and store column information table */
-	create_colinfo (L, cur);
+	if(create_colinfo (L, cur) < 0) {
+		lua_pop(L, 1);
+		return fail(L, hSTMT, cur->hstmt);
+	}
 
-    return 1;
+	return 1;
 }
 
 
@@ -453,7 +464,7 @@ static int conn_close (lua_State *L) {
 */
 static int conn_execute (lua_State *L) {
 	conn_data *conn = (conn_data *) getconnection (L);
-	const char *statement = luaL_checkstring(L, 2);
+	SQLCHAR *statement = (SQLCHAR*)luaL_checkstring(L, 2);
 	SQLHDBC hdbc = conn->hdbc;
 	SQLHSTMT hstmt;
 	SQLSMALLINT numcols;
@@ -462,7 +473,7 @@ static int conn_execute (lua_State *L) {
 	if (error(ret))
 		return fail(L, hDBC, hdbc);
 
-	ret = SQLPrepare(hstmt, (char *) statement, SQL_NTS);
+	ret = SQLPrepare(hstmt, statement, SQL_NTS);
 	if (error(ret)) {
 		ret = fail(L, hSTMT, hstmt);
 		SQLFreeHandle(hSTMT, hstmt);
@@ -583,9 +594,9 @@ static int create_connection (lua_State *L, int o, env_data *env, SQLHDBC hdbc)
 */
 static int env_connect (lua_State *L) {
 	env_data *env = (env_data *) getenvironment (L);
-	const char *sourcename = luaL_checkstring (L, 2);
-	const char *username = luaL_optstring (L, 3, NULL);
-	const char *password = luaL_optstring (L, 4, NULL);
+	SQLCHAR *sourcename = (SQLCHAR*)luaL_checkstring (L, 2);
+	SQLCHAR *username = (SQLCHAR*)luaL_optstring (L, 3, NULL);
+	SQLCHAR *password = (SQLCHAR*)luaL_optstring (L, 4, NULL);
 	SQLHDBC hdbc;
 	SQLRETURN ret;
 
@@ -595,8 +606,8 @@ static int env_connect (lua_State *L) {
 		return luasql_faildirect (L, "connection allocation error.");
 
 	/* tries to connect handle */
-	ret = SQLConnect (hdbc, (char *) sourcename, SQL_NTS, 
-		(char *) username, SQL_NTS, (char *) password, SQL_NTS);
+	ret = SQLConnect (hdbc, sourcename, SQL_NTS, 
+		username, SQL_NTS, password, SQL_NTS);
 	if (error(ret)) {
 		ret = fail(L, hDBC, hdbc);
 		SQLFreeHandle(hDBC, hdbc);