Cannot Insert Large Text Into Database Memo Field

I'm trying to insert this text into a memo field:

Set cnn = CreateObject("ADODB.Connection")
str = Server.MapPath("database/alumni.mdb")
strDB = "Provider=MICROSOFT.JET.OLEDB.4.0;Data Source=" & str
cnn.Open strDB
Set rst = CreateObject("ADODB.Recordset")

sql = "INSERT INTO tblMessage (MessageID, UserID, PostTypeID, Subject,
DatePosted, MessageText, Active) Values ('" & vMessageID & "','" &
vUser & "', " & vPostType & ",'" & vSubject & "','" & vDatePosted &
"','" & vMessageText & "',0)"

rst.Open sql, cnn, adOpenStatic, adLockOptimistic

vMessageText = "This is a test just to see if it will blow up on a
large comment. Just testing again. Don't mind me."

Can I put this into my database field or is it too much and if not,
how do I solve this issue. I need to be able to post messages and
input for large fields.