Consuming axis webservice works in ColdFusion 8, not in ColdFusion 7 - same exact code

I have the same CFML code that I used to invoke a webservice in ColdFusion 8 that works fine.
I think it's a java version related issue (ColdFusion 7 uses JDK 1.4, ColdFusion 8 uses JDK 1.6).

When I deploy this in a ColdFusion 7 server, I get an illegal argument exception:

Could not perform web service invocation "insertUpdateDnbCompany".
Here is the fault returned when invoking the web service operation:

java.lang.IllegalArgumentException: argument type mismatch

Here's the stack trace:

java.lang.IllegalArgumentException: argument type mismatch
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at coldfusion.xml.rpc.ServiceProxy.invokeImpl(ServiceProxy.java:223)
at coldfusion.xml.rpc.ServiceProxy.invoke(ServiceProxy.java:153)
at coldfusion.runtime.CfJspPage._invoke(CfJspPage.java:1634)
at cfReplicate22ecfm975370412.runPage(E:\Inetpub\wwwroot\webapps_NEW\MDM\Replicate2.cfm:11)
at coldfusion.runtime.CfJspPage.invoke(CfJspPage.java:152)
at coldfusion.tagext.lang.IncludeTag.doStartTag(IncludeTag.java:349)
at coldfusion.filter.CfincludeFilter.invoke(CfincludeFilter.java:65)
at coldfusion.filter.ApplicationFilter.invoke(ApplicationFilter.java:225)
at coldfusion.filter.RequestMonitorFilter.invoke(RequestMonitorFilter.java:51)
at coldfusion.filter.PathFilter.invoke(PathFilter.java:86)
at coldfusion.filter.ExceptionFilter.invoke(ExceptionFilter.java:69)
at coldfusion.filter.BrowserDebugFilter.invoke(BrowserDebugFilter.java:52)
at coldfusion.filter.ClientScopePersistenceFilter.invoke(ClientScopePersistenceFilter.java:28)
at coldfusion.filter.BrowserFilter.invoke(BrowserFilter.java:38)
at coldfusion.filter.GlobalsFilter.invoke(GlobalsFilter.java:38)
at coldfusion.filter.DatasourceFilter.invoke(DatasourceFilter.java:22)
at coldfusion.filter.RequestThrottleFilter.invoke(RequestThrottleFilter.java:115)
at coldfusion.CfmServlet.service(CfmServlet.java:107)
at coldfusion.bootstrap.BootstrapServlet.service(BootstrapServlet.java:78)
at jrun.servlet.ServletInvoker.invoke(ServletInvoker.java:91)
at jrun.servlet.JRunInvokerChain.invokeNext(JRunInvokerChain.java:42)
at jrun.servlet.JRunRequestDispatcher.invoke(JRunRequestDispatcher.java:257)
at jrun.servlet.ServletEngineService.dispatch(ServletEngineService.java:541)
at jrun.servlet.jrpp.JRunProxyService.invokeRunnable(JRunProxyService.java:204)
at jrunx.scheduler.ThreadPool$DownstreamMetrics.invokeRunnable(ThreadPool.java:318)
at jrunx.scheduler.ThreadPool$ThreadThrottle.invokeRunnable(ThreadPool.java:426)
at jrunx.scheduler.ThreadPool$UpstreamMetrics.invokeRunnable(ThreadPool.java:264)
at jrunx.scheduler.WorkerThread.run(WorkerThread.java:66)