This happened to me in Windows too, and it was solved by changing the jety-env.xml file. I changed it to used some specific directory in windows instead of ".".
<Call name="getConfiguration" class="bitronix.tm.TransactionManagerServices">
<Set name="serverId">jetty-btm-node0</Set>
<Set name="logPart1Filename">
C:/tmp/btm1.tlog
</Set>
<Set name="logPart2Filename">
C:/tmp/btm2.tlog
</Set>
</Call>