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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001179110-09-012549.txt : 20090825
<SEC-HEADER>0001179110-09-012549.hdr.sgml : 20090825
<ACCEPTANCE-DATETIME>20090825174643
ACCESSION NUMBER:		0001179110-09-012549
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061003
FILED AS OF DATE:		20090825
DATE AS OF CHANGE:		20090825

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DUNSMORE JOSEPH T
		CENTRAL INDEX KEY:			0001204098

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34033
		FILM NUMBER:		091034762

	MAIL ADDRESS:	
		STREET 1:		11001 BREN RD. EAST
		CITY:			MINNETONKA
		STATE:			MN
		ZIP:			55343

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DIGI INTERNATIONAL INC
		CENTRAL INDEX KEY:			0000854775
		STANDARD INDUSTRIAL CLASSIFICATION:	COMPUTER COMMUNICATIONS EQUIPMENT [3576]
		IRS NUMBER:				411532464
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		11001 BREN ROAD EAST
		CITY:			MINNETONKA
		STATE:			MN
		ZIP:			55343
		BUSINESS PHONE:		6129123444

	MAIL ADDRESS:	
		STREET 1:		11001 BREN ROAD EAST
		CITY:			MINNETONKA
		STATE:			MN
		ZIP:			55343
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4/A -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2006-10-03</periodOfReport>

    <dateOfOriginalSubmission>2007-08-10</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000854775</issuerCik>
        <issuerName>DIGI INTERNATIONAL INC</issuerName>
        <issuerTradingSymbol>DGII</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001204098</rptOwnerCik>
            <rptOwnerName>DUNSMORE JOSEPH T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>11001 BREN ROAD EAST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MINNETONKA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55343</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman, President and CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-10-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>303.235</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>10.95</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7619.974</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Employee Stock Purchase Plan acquisition.</footnote>
        <footnote id="F2">The original Form 4 mistakenly reported the number of shares acquired as 302.235, which is one share less than the number of shares actually acquired.  The incorrect balance was carried forward in subsequent Form 4s.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Joseph T. Dunsmore</signatureName>
        <signatureDate>2009-08-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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