I copied and pasted a changelist number as being the first to track.
I didn't notice that I had included a space.
Perhaps the string should be trimmed of spaces before attempting to convert it
to an integer value?

java.lang.NumberFormatException: For input string: "1756317 "
at java.lang.NumberFormatException.forInputString(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.(Unknown Source)
at
hudson.plugins.perforce.PerforceSCM$PerforceSCMDescriptor.newInstance(PerforceSCM.java:463)
at
hudson.plugins.perforce.PerforceSCM$PerforceSCMDescriptor.newInstance(PerforceSCM.java:438)
at hudson.model.Descriptor.newInstance(Descriptor.java:176)
at hudson.scm.SCMS.parseSCM(SCMS.java:38)
at hudson.model.AbstractProject.submit(AbstractProject.java:1003)
at hudson.model.Project.submit(Project.java:161)
at hudson.model.FreeStyleProject.submit(FreeStyleProject.java:68)
at hudson.model.Job.doConfigSubmit(Job.java:856)
at hudson.model.AbstractProject.doConfigSubmit(AbstractProject.java:320)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:103)
at org.kohsuke.stapler.Function.bindAndinvoke(Function.java:57)
at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:75)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:409)
at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:173)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:409)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:352)
at org.kohsuke.stapler.Stapler.service(Stapler.java:112)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:249)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:335)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:378)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:61)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:53)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:88)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:244)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
at java.lang.Thread.run(Unknown Source)