OK, well then, the only way that I can see to do it with SMO is through a manual semi-shallow copy, like this:

Imports Microsoft.SqlServer

Imports Microsoft.SqlServer.Management

Imports Microsoft.SqlServer.Management.Common

Imports Microsoft.SqlServer.Management.Smo

Imports Microsoft.SqlServer.Server

Imports system.Data

Module Util

Public Sub ColumnDef_Copy(ByVal SourceTable As Smo.Table _

, ByVal TargetTable As Smo.Table _

, ByVal ColName As String)

'copies a column definition from one table to another an then updates the

' target tables defintion in the database.

'

'2008-05-07 BYoung Created.

'

'NOTE: untested.

Dim SourceCol As Smo.Column = SourceTable.Columns(ColName)

Dim TargetCol As New Smo.Column(TargetTable, ColName)

'set the target column's properties using a Shallow Copy:

With SourceCol

TargetCol.DataType = .DataType

TargetCol.Collation = .Collation

If .Computed Then

TargetCol.Computed = .Computed

TargetCol.ComputedText = .ComputedText

TargetCol.IsPersisted = .IsPersisted

End If

TargetCol.Default = .Default

TargetCol.DefaultSchema = .DefaultSchema

For Each xp As Smo.ExtendedProperty In .ExtendedProperties

TargetCol.ExtendedProperties.Add( _

New Smo.ExtendedProperty(TargetCol, xp.Name, xp.Value))

Next

If .Identity Then

TargetCol.Identity = .Identity

TargetCol.IdentityIncrement = .IdentityIncrement

TargetCol.IdentitySeed = .IdentitySeed

End If

TargetCol.NotForReplication = .NotForReplication

TargetCol.Nullable = .Nullable

TargetCol.RowGuidCol = .RowGuidCol

TargetCol.Rule = .Rule

TargetCol.RuleSchema = .RuleSchema

End With

'Find the column's position

Dim ord As Integer = 0

While SourceTable.Columns.Item(ord) IsNot SourceCol

ord += 1

End While

TargetTable.Columns.Add(TargetCol, ord)

TargetTable.Alter()

End Sub

End Module

You will have to test this yourself.