NullPointerException when spidering a context

[GoogleCodeExporter]

Steps to reproduce the issue:
1. Run ZAP;
2. Access a site;
3. Select the accessed site (in the "Sites" tab or "History" tab) and include 
it in a context (context "1");
4. Right click in the "Sites" tab and select the option "Attack" > "Spider 
Context..." > "1".
5. Note that the spider has started but nothing happens; Check the log file (or 
the "Output" tab), there should be a NullPointerException:
[...]
22341 [Thread-8] INFO org.zaproxy.zap.spider.Spider  - Spider initializing...
22350 [Thread-8] ERROR org.zaproxy.zap.ZAP$UncaughtExceptionLogger  - Exception 
in thread "Thread-8"
java.lang.NullPointerException
    at org.zaproxy.zap.spider.Spider.addSeed(Spider.java:173)
    at org.zaproxy.zap.extension.spider.SpiderThread.startSpider(SpiderThread.java:218)
    at org.zaproxy.zap.extension.spider.SpiderThread.runScan(SpiderThread.java:121)
    at org.zaproxy.zap.extension.spider.SpiderThread.run(SpiderThread.java:110)
[...]

ZAP Version:
Trunk (tested with latest revision r3036) and some weekly releases.

Original issue reported on code.google.com by THC...@gmail.com on 10 Apr 2013 at 1:20

[GoogleCodeExporter]

Original comment by cosminst...@gmail.com on 10 Apr 2013 at 9:22

• Changed state: Started

[GoogleCodeExporter]

Committed in r3038.

Original comment by cosminst...@gmail.com on 10 Apr 2013 at 9:28

• Changed state: Committed

[GoogleCodeExporter]

Original comment by psii...@gmail.com on 15 Apr 2013 at 8:46

• Added labels: Build-20130415

[GoogleCodeExporter]

Fixed in 2.1.0

Original comment by psii...@gmail.com on 18 Apr 2013 at 9:49

• Changed state: Fixed