kernel32 内のは動く (1.1.5、2.0)
ttp://www.oooforum.org/forum/viewtopic.phtml?t=72220&highlight=kernel32

Declare Function GetComputerName Lib "kernel32" Alias "GetComputerNameA" _
(ByRef lpbuffer As String, nSize As Long) As Long

Public Function ComputerName() As String
Dim sBuffer As String
Dim lSize As Long
Dim sNome As String

sBuffer = Space$(260)
lSize = Len(sBuffer)
Call GetComputerName(sBuffer, lSize)
If lSize > 0 Then
sNome = Left$(sBuffer, lSize)
lSize = InStr(sNome, Chr$(0))
If lSize Then
sNome = Left$(sNome, lSize - 1)
End If
Else
sNome= ""
End If
'ComputerName = sNome
MsgBox sNome
End Function

bregexp のときの Declare 時の引数を ByRef だの ByVal をいじっても特に変わりなし
相性悪いんかね・・・