diff --git a/phpBB/includes/db/mssql.php b/phpBB/includes/db/mssql.php
index b7178593dc..bc0a870885 100644
--- a/phpBB/includes/db/mssql.php
+++ b/phpBB/includes/db/mssql.php
@@ -355,34 +355,44 @@ class dbal_mssql extends dbal
 	*/
 	function _sql_error()
 	{
-		$error = array(
-			'message'	=> @mssql_get_last_message(),
-			'code'		=> ''
-		);
-
-		// Get error code number
-		$result_id = @mssql_query('SELECT @@ERROR as code', $this->db_connect_id);
-		if ($result_id)
+		if (function_exists('mssql_get_last_message'))
 		{
-			$row = @mssql_fetch_assoc($result_id);
-			$error['code'] = $row['code'];
-			@mssql_free_result($result_id);
-		}
+			$error = array(
+				'message'	=> @mssql_get_last_message(),
+				'code'		=> ''
+			);
 
-		// Get full error message if possible
-		$sql = 'SELECT CAST(description as varchar(255)) as message
-			FROM master.dbo.sysmessages
-			WHERE error = ' . $error['code'];
-		$result_id = @mssql_query($sql);
-		
-		if ($result_id)
-		{
-			$row = @mssql_fetch_assoc($result_id);
-			if (!empty($row['message']))
+			// Get error code number
+			$result_id = @mssql_query('SELECT @@ERROR as code', $this->db_connect_id);
+			if ($result_id)
 			{
-				$error['message'] .= '<br />' . $row['message'];
+				$row = @mssql_fetch_assoc($result_id);
+				$error['code'] = $row['code'];
+				@mssql_free_result($result_id);
 			}
-			@mssql_free_result($result_id);
+
+			// Get full error message if possible
+			$sql = 'SELECT CAST(description as varchar(255)) as message
+				FROM master.dbo.sysmessages
+				WHERE error = ' . $error['code'];
+			$result_id = @mssql_query($sql);
+
+			if ($result_id)
+			{
+				$row = @mssql_fetch_assoc($result_id);
+				if (!empty($row['message']))
+				{
+					$error['message'] .= '<br />' . $row['message'];
+				}
+				@mssql_free_result($result_id);
+			}
+		}
+		else
+		{
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
 		}
 
 		return $error;
diff --git a/phpBB/includes/db/mssql_odbc.php b/phpBB/includes/db/mssql_odbc.php
index dabdbd1a44..e1234389df 100644
--- a/phpBB/includes/db/mssql_odbc.php
+++ b/phpBB/includes/db/mssql_odbc.php
@@ -360,10 +360,20 @@ class dbal_mssql_odbc extends dbal
 	*/
 	function _sql_error()
 	{
-		return array(
-			'message'	=> @odbc_errormsg(),
-			'code'		=> @odbc_error()
-		);
+		if (function_exists('odbc_errormsg'))
+		{
+			return array(
+				'message'	=> @odbc_errormsg(),
+				'code'		=> @odbc_error()
+			);
+		}
+		else
+		{
+			return array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
+		}
 	}
 
 	/**
diff --git a/phpBB/includes/db/mysql.php b/phpBB/includes/db/mysql.php
index ae36fe6425..7314e92087 100644
--- a/phpBB/includes/db/mysql.php
+++ b/phpBB/includes/db/mysql.php
@@ -439,10 +439,20 @@ class dbal_mysql extends dbal
 	{
 		if (!$this->db_connect_id)
 		{
-			return array(
-				'message'	=> @mysql_error(),
-				'code'		=> @mysql_errno()
-			);
+			if (function_exists('mysql_error'))
+			{
+				return array(
+					'message'	=> @mysql_error(),
+					'code'		=> @mysql_errno()
+				);
+			}
+			else
+			{
+				return array(
+					'message'	=> $this->connect_error,
+					'code'		=> '',
+				);
+			}
 		}
 
 		return array(
diff --git a/phpBB/includes/db/oracle.php b/phpBB/includes/db/oracle.php
index 42f5de1b24..b234d8b45e 100644
--- a/phpBB/includes/db/oracle.php
+++ b/phpBB/includes/db/oracle.php
@@ -674,17 +674,27 @@ class dbal_oracle extends dbal
 	*/
 	function _sql_error()
 	{
-		$error = @ocierror();
-		$error = (!$error) ? @ocierror($this->query_result) : $error;
-		$error = (!$error) ? @ocierror($this->db_connect_id) : $error;
-
-		if ($error)
+		if (function_exists('ocierror'))
 		{
-			$this->last_error_result = $error;
+			$error = @ocierror();
+			$error = (!$error) ? @ocierror($this->query_result) : $error;
+			$error = (!$error) ? @ocierror($this->db_connect_id) : $error;
+
+			if ($error)
+			{
+				$this->last_error_result = $error;
+			}
+			else
+			{
+				$error = (isset($this->last_error_result) && $this->last_error_result) ? $this->last_error_result : array();
+			}
 		}
 		else
 		{
-			$error = (isset($this->last_error_result) && $this->last_error_result) ? $this->last_error_result : array();
+			$error = array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
 		}
 
 		return $error;
diff --git a/phpBB/includes/db/sqlite.php b/phpBB/includes/db/sqlite.php
index be0ad4fc8f..3c9b2cce34 100644
--- a/phpBB/includes/db/sqlite.php
+++ b/phpBB/includes/db/sqlite.php
@@ -300,10 +300,20 @@ class dbal_sqlite extends dbal
 	*/
 	function _sql_error()
 	{
-		return array(
-			'message'	=> @sqlite_error_string(@sqlite_last_error($this->db_connect_id)),
-			'code'		=> @sqlite_last_error($this->db_connect_id)
-		);
+		if (function_exists('sqlite_error_string'))
+		{
+			return array(
+				'message'	=> @sqlite_error_string(@sqlite_last_error($this->db_connect_id)),
+				'code'		=> @sqlite_last_error($this->db_connect_id)
+			);
+		}
+		else
+		{
+			return array(
+				'message'	=> $this->connect_error,
+				'code'		=> '',
+			);
+		}
 	}
 
 	/**