XWikiHibernateAttachmentStore methods don't take into account attachment wiki as well as they think

Failed to load content for attachment [header.png@subwiki » ColorThemes » DefaultColorTheme]. This attachment is broken, please consider re-uploading it. Internal error: Error number 3231 in 3: Exception while loading attachment header.png of document ColorThemes.DefaultColorTheme
Failed to load content for attachment [logo.png@subwiki » ColorThemes » DefaultColorTheme]. This attachment is broken, please consider re-uploading it. Internal error: Error number 3231 in 3: Exception while loading attachment logo.png of document ColorThemes.DefaultColorTheme
Failed to load attachments
class java.lang.RuntimeException: Failed to compare attachments with reference [Attachment subwiki:ColorThemes.DefaultColorTheme@header.png] 
at com.xpn.xwiki.doc.XWikiDocument.equalsData(XWikiDocument.java:3908)
 at org.xwiki.extension.xar.internal.handler.XarExtensionJobFinishedListener.onEvent(XarExtensionJobFinishedListener.java:193) 
at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:304) 
at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:269) 
at org.xwiki.job.internal.AbstractJob.jobFinished(AbstractJob.java:260) 
at org.xwiki.job.internal.AbstractJob.runInContext(AbstractJob.java:214) 
at org.xwiki.job.internal.AbstractJob.run(AbstractJob.java:192) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: class com.xpn.xwiki.XWikiException: Error number 0 in 2: Failed to compare attachments 
at com.xpn.xwiki.doc.XWikiAttachment.equalsData(XWikiAttachment.java:954) 
at com.xpn.xwiki.doc.XWikiDocument.equalsData(XWikiDocument.java:3904)
at org.xwiki.extension.xar.internal.handler.XarExtensionJobFinishedListener.onEvent(XarExtensionJobFinishedListener.java:193) 
at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:304)
at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:269) 
at org.xwiki.job.internal.AbstractJob.jobFinished(AbstractJob.java:260) 
at org.xwiki.job.internal.AbstractJob.runInContext(AbstractJob.java:214) 
at org.xwiki.job.internal.AbstractJob.run(AbstractJob.java:192) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) 

Caused by: class java.lang.NullPointerException: null
at com.xpn.xwiki.doc.XWikiAttachment.getContentInputStream(XWikiAttachment.java:690) 
at com.xpn.xwiki.doc.XWikiAttachment.equalsData(XWikiAttachment.java:939) 
at com.xpn.xwiki.doc.XWikiDocument.equalsData(XWikiDocument.java:3904)
at org.xwiki.extension.xar.internal.handler.XarExtensionJobFinishedListener.onEvent(XarExtensionJobFinishedListener.java:193)
at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:304)
at org.xwiki.observation.internal.DefaultObservationManager.notify(DefaultObservationManager.java:269) 
at org.xwiki.job.internal.AbstractJob.jobFinished(AbstractJob.java:260) 
at org.xwiki.job.internal.AbstractJob.runInContext(AbstractJob.java:214) 
at org.xwiki.job.internal.AbstractJob.run(AbstractJob.java:192) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745)