Convert ASP.NET function code to PHP

Task is to convert this ASP.NET function into PHP5 compatible code. I have provided a sample encrypted string that you can use to test your PHP code. Lowest bid will get the job, this is easy I just can't be bothered. decrypt this string "s9FJB7lQTGkk1Lz6KoKfw5qSsuubEqq5" using key "free1234" Private key() As Byte = {} Private IV() As Byte = {&H12, &H34, &H56, &H78, &H90, &HAB, &HCD, &HEF} Public Function Decrypt(ByVal stringToDecrypt As String, _ ByVal sEncryptionKey As String) As String Dim inputByteArray([login to view URL]) As Byte Try key = [login to view URL](Left(sEncryptionKey, 8)) Dim des As New [login to view URL]() inputByteArray = base64_decode(stringToDecrypt) Dim ms As New [login to view URL]() Dim cs As New [login to view URL](ms, [login to view URL](key, IV), _ [login to view URL]) [login to view URL](inputByteArray, 0, [login to view URL]) [login to view URL]() Dim encoding As [login to view URL] = [login to view URL] Return [login to view URL]([login to view URL]()) Catch e As Exception Return [login to view URL] End Try End Function