Type mismatch between indexed read and indexed write methods

Hey there,

when using your Aspose pdf example - TableInHeaderFooter code, the following error occurs on this line:
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Section sec1 = pdf1.getSections().add()

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2014-08-25 11:28:02,920 [http-bio-8080-exec-8] ERROR errors.GrailsExceptionResolver  - IntrospectionException occurred when processing request: [GET] /rest.services-is.eis/students/1
type mismatch between indexed read and indexed write methods: _Item. Stacktrace follows:
Message: type mismatch between indexed read and indexed write methods: _Item
    Line | Method
->>  387 | findIndexedPropertyType    in java.beans.IndexedPropertyDescriptor
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|    215 | setIndexedReadMethod       in     ''
|    471 | <init> . . . . . . . . . . in     ''
|    647 | processPropertyDescriptors in java.beans.Introspector
|    543 | getTargetPropertyInfo . .  in     ''
|    418 | getBeanInfo                in     ''
|    163 | getBeanInfo . . . . . . .  in     ''
|     19 | createStudentProfilePdf    in com.scmt.util.Reporting$$EOnwNrZE
|     79 | $tt__show . . . . . . . .  in rest.services.is.eis.StudentController
|    198 | doFilter                   in grails.plugin.cache.web.filter.PageFragmentCachingFilter
|     63 | doFilter . . . . . . . . . in grails.plugin.cache.web.filter.AbstractFilter
|   1145 | runWorker                  in java.util.concurrent.ThreadPoolExecutor
|    615 | run . . . . . . . . . . .  in java.util.concurrent.ThreadPoolExecutor$Worker
^    745 | run                        in java.lang.Thread
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As you can see, I am using REST Services under Grails.
I am building an example application which will decide if we use Aspose in our future projects. Thus I still am using the trial version of Aspose.

My setup:

• IntelliJ IDEA 13.1.4
• Java 1.7.0_67
• Grails 2.3.9
  

Any idea why this happens? I even updated to the latest JDK.

Thank you in advance.