Recursive Query --- Very Urgent

Hello. I have a question. I have a table that keeps track of
claims being made by clients (like insurance claims). There is a table which
has 2 fields. Field1 and Field2. Field1 has the original claim number. If an
adjustment is made to the claim, a new claim number will be generated. For example
if a person pays $100 and files a claim, he is issued a claim number which goes
into Field1. If that person spends some more money towards the same issue and
then files another claim then he is given a new claim number which is stored in
Field2.

Field1--------------Field2

--------------------------------

100--------------------150

150--------------------200

200--------------------250

250--------------------Null (No more adjustments made)

and so on.

So in the query I will supply a claim number (say 100). I
need to get the history of all the claims attached to it. In this example 100,
150, 200, 250.

Also if the claim number provided is 200 I need to get the
original claim number (which is 100) meaning I need to back track and forward
track too. I need this in SQL Server 2000.

I hope I am clear enough. Thanks.