diff --git a/src/documentation/content/xdocs/status.xml b/src/documentation/content/xdocs/status.xml
index ef158f1f9..44524a32a 100644
--- a/src/documentation/content/xdocs/status.xml
+++ b/src/documentation/content/xdocs/status.xml
@@ -34,6 +34,7 @@
 
     <changes>
         <release version="3.8-beta1" date="2010-??-??">
+           <action dev="poi-developers" type="fix">50795 - Avoid NPE from xmlbeans when moving XSSF Comments from one cell to another</action>
            <action dev="poi-developers" type="fix">46664 - When creating HSSF Print Areas, ensure the named range is reference based not value based</action>
            <action dev="poi-developers" type="fix">50756 - When formatting numbers based on their Cell Style, treat GENERAL the same as the more typical General</action>
            <action dev="poi-developers" type="fix">fixed HSSFWorkbook.createCellStyle to throw exception if the maximum number of cell styles was exceeded</action>
diff --git a/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFComment.java b/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFComment.java
index 9d6c34cd4..f75b25062 100644
--- a/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFComment.java
+++ b/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFComment.java
@@ -116,7 +116,16 @@ public class XSSFComment implements Comment {
         _comment.setRef(ref.formatAsString());
         _comments.referenceUpdated(oldRef, _comment);
         
-        if(_vmlShape != null) _vmlShape.getClientDataArray(0).setColumnArray(0, new BigInteger(String.valueOf(col)));
+        if(_vmlShape != null) {
+           _vmlShape.getClientDataArray(0).setColumnArray(
+                 new BigInteger[] { new BigInteger(String.valueOf(col)) }
+           );
+           
+           // There is a very odd xmlbeans bug when changing the column
+           //  arrays which can lead to corrupt pointer
+           // This call seems to fix them again... See bug #50795
+           _vmlShape.getClientDataList().toString();
+        }
 	}
 
     /**
diff --git a/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFBugs.java b/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFBugs.java
index b45a5df6c..abc9fc73b 100644
--- a/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFBugs.java
+++ b/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFBugs.java
@@ -620,4 +620,56 @@ public final class TestXSSFBugs extends BaseTestBugzillaIssues {
        assertEquals("SUM(\n1,2\n)", c.getCellFormula());
        assertEquals(3.0, c.getNumericCellValue());
     }
+    
+    /**
+     * Moving a cell comment from one cell to another
+     */
+    public void test50795() throws Exception {
+       XSSFWorkbook wb = XSSFTestDataSamples.openSampleWorkbook("50795.xlsx");
+       XSSFSheet sheet = wb.getSheetAt(0);
+       XSSFRow row = sheet.getRow(0);
+
+       XSSFCell cellWith = row.getCell(0);
+       XSSFCell cellWithoutComment = row.getCell(1);
+       
+       assertNotNull(cellWith.getCellComment());
+       assertNull(cellWithoutComment.getCellComment());
+       
+       String exp = "\u0410\u0432\u0442\u043e\u0440:\ncomment";
+       XSSFComment comment = cellWith.getCellComment();
+       assertEquals(exp, comment.getString().getString());
+       
+       
+       // Check we can write it out and read it back as-is
+       wb = XSSFTestDataSamples.writeOutAndReadBack(wb);
+       sheet = wb.getSheetAt(0);
+       row = sheet.getRow(0);
+       cellWith = row.getCell(0);
+       cellWithoutComment = row.getCell(1);
+       
+       // Double check things are as expected
+       assertNotNull(cellWith.getCellComment());
+       assertNull(cellWithoutComment.getCellComment());
+       comment = cellWith.getCellComment();
+       assertEquals(exp, comment.getString().getString());
+
+       
+       // Move the comment
+       cellWithoutComment.setCellComment(comment);
+       
+       
+       // Write out and re-check
+       wb = XSSFTestDataSamples.writeOutAndReadBack(wb);
+       sheet = wb.getSheetAt(0);
+       row = sheet.getRow(0);
+       
+       // Ensure it swapped over
+       cellWith = row.getCell(0);
+       cellWithoutComment = row.getCell(1);
+       assertNull(cellWith.getCellComment());
+       assertNotNull(cellWithoutComment.getCellComment());
+       
+       comment = cellWithoutComment.getCellComment();
+       assertEquals(exp, comment.getString().getString());
+    }
 }
diff --git a/test-data/spreadsheet/50795.xlsx b/test-data/spreadsheet/50795.xlsx
new file mode 100644
index 000000000..a58aeec7c
Binary files /dev/null and b/test-data/spreadsheet/50795.xlsx differ