Insert 4 tinyint values into varbinary(4) I'm working on a function to convert the string representation of an IP into its varbinary(4/16) form.

Right now, I have this:

@stringIP = '192.168.0.3'
select 
    CAST(PARSENAME(@stringIP, 4) as tinyint),
    CAST(PARSENAME(@stringIP, 3) as tinyint),
    CAST(PARSENAME(@stringIP, 2) as tinyint),
    CAST(PARSENAME(@stringIP, 1) as tinyint)


This breaks up my IPv4 Address very well; but I need to figure out how to insert it into a varbinary(4) so I can insert the data to my table. I cannot find ANY TSQL syntax to combine these four tinyints into a varbinary(4) -- I can only find C#/VB examples using paramterized SQL. This is fine and good, but I'm trying to create an SQL Function do use in an INSTEAD OF INSERT trigger.
@stringIP = '192.168.0.3'
select 
    cast(CAST(PARSENAME(@stringIP, 4) as tinyint) as varbinary(1)) +
    cast(CAST(PARSENAME(@stringIP, 3) as tinyint) as varbinary(1)) +
    cast(CAST(PARSENAME(@stringIP, 2) as tinyint) as varbinary(1)) +
    cast(CAST(PARSENAME(@stringIP, 1) as tinyint) as varbinary(1))