[Galaxy S III Android Development] MattBooth:
I figured out my FC problems, pinguy. It was to do with CSC and the AOSP Browser.

If you make the contents of customer.xml into this:

<?xml version="1.0" encoding="UTF-8" ?>
<CustomerData>
<GeneralInfo>
<CSCEdition>ED008</CSCEdition>
<Country>UK</Country>
<CountryISO>GB</CountryISO>
<Region>EUR</Region>
<SalesCode>H3G</SalesCode>
<NbNetworkInfo>1</NbNetworkInfo>
<NetworkInfo>
<MCCMNC>23420</MCCMNC>
<NetworkName>3</NetworkName>
</NetworkInfo>
</GeneralInfo>
<Settings>
<Main>
<Security>
<NbNetworkLock>2</NbNetworkLock>
<NetworkLock>23420</NetworkLock>
<NetworkLock>23594</NetworkLock>
</Security>
<Network>
<NbFastDormancy>2</NbFastDormancy>
<FastDormancy>
<NetworkName>3</NetworkName>
<FastDormancyEnableStatus>on</FastDormancyEnableStatus>
<LCDStatus>on</LCDStatus>
</FastDormancy>
<FastDormancy>
<NetworkName>3</NetworkName>
<FastDormancyEnableStatus>on</FastDormancyEnableStatus>
<LCDStatus>off</LCDStatus>
</FastDormancy>
<NbWbAmr>1</NbWbAmr>
<WbAmr>
<NetworkName>3</NetworkName>
<WbAmrCodec>on</WbAmrCodec>
</WbAmr>
<NbSOSNumber>3</NbSOSNumber>
<SOSNumber>999</SOSNumber>
<SOSNumber>911</SOSNumber>
<SOSNumber>112</SOSNumber>
<AutoProfile>off</AutoProfile>
</Network>
<Sound>
<RngVolume>5</RngVolume>
<ExtraSound>
<ConnectTone>on</ConnectTone>
<MinuteMind>off</MinuteMind>
</ExtraSound>
</Sound>
<Phone>
<DefLanguage>english</DefLanguage>
<DefLanguageNoSIM>english</DefLanguageNoSIM>
<BackLightTime>30sec</BackLightTime>
<DateTimeFormat>
<DateFormat>ddmmyyyy</DateFormat>
<TimeFormat>12h</TimeFormat>
<TimezoneUpdate>off</TimezoneUpdate>
</DateTimeFormat>
<AutoSyncCommon>on</AutoSyncCommon>
<VisiblePassword>on</VisiblePassword>
</Phone>
</Main>
<Calendar>
<StartDay>monday</StartDay>
</Calendar>
<Messages>
<NbVoicemail>1</NbVoicemail>
<Voicemail>
<NetworkName>default</NetworkName>
<TelNum>+447782333123</TelNum>
</Voicemail>
<PushMsg>
<RecOption>off</RecOption>
</PushMsg>
<SMS>
<DeliveryReport>off</DeliveryReport>
<MsgTypeThreshold>
<ThresholdValue>12</ThresholdValue>
<ThresholdType>pagecount</ThresholdType>
</MsgTypeThreshold>
<CharSupport>gsmalpha</CharSupport>
<SSMS>off</SSMS>
<DeleteOldMessage>off</DeleteOldMessage>
</SMS>
<MMS>
<MmsSending>
<ReqDeliveryRep>off</ReqDeliveryRep>
<ReqReadRep>off</ReqReadRep>
<CreationMode>warning</CreationMode>
</MmsSending>
<MmsReceiving>
<Home>auto</Home>
<Roaming>auto</Roaming>
</MmsReceiving>
</MMS>
</Messages>
<GPS>
<GPSActivation>off</GPSActivation>
</GPS>
<ActiveSync>
<Signature>Sent from Galaxy S3 on Three</Signature>
<SyncSchedule>
<PeakDuration>15m</PeakDuration>
<OffPeakDuration>15m</OffPeakDuration>
</SyncSchedule>
</ActiveSync>
<Browser>
<NbBookmark>6</NbBookmark>
<Bookmark>
<NetworkName>default</NetworkName>
<Editable>yes</Editable>
<Index>1</Index>
<BookmarkName>Games</BookmarkName>
<URL>http://wap.uk.samsungmobile.com/bm/games</URL>
</Bookmark>
<Bookmark>
<NetworkName>default</NetworkName>
<Editable>yes</Editable>
<Index>2</Index>
<BookmarkName>Ringtones</BookmarkName>
<URL>http://wap.uk.samsungmobile.com/bm/ringtones</URL>
</Bookmark>
<Bookmark>
<NetworkName>default</NetworkName>
<Editable>yes</Editable>
<Index>3</Index>
<BookmarkName>Screensavers</BookmarkName>
<URL>http://wap.uk.samsungmobile.com/bm/screensavers</URL>
</Bookmark>
<Bookmark>
<NetworkName>default</NetworkName>
<Editable>yes</Editable>
<Index>4</Index>
<BookmarkName>Videos</BookmarkName>
<URL>http://wap.uk.samsungmobile.com/bm/videos</URL>
</Bookmark>
<Bookmark>
<NetworkName>default</NetworkName>
<Editable>yes</Editable>
<Index>5</Index>
<BookmarkName>Wallpapers</BookmarkName>
<URL>http://wap.uk.samsungmobile.com/bm/wallpapers</URL>
</Bookmark>
<Bookmark>
<NetworkName>default</NetworkName>
<Editable>yes</Editable>
<Index>6</Index>
<BookmarkName>Yahoo!</BookmarkName>
<URL>http://m.yahoo.com/?tsrc=samsungbm</URL>
</Bookmark>
<eManual>
<URL>http://www.samsung.com/m-manual/common</URL>
</eManual>
</Browser>
<Connections>
<NbProfileHandle>1</NbProfileHandle>
<ProfileHandle>
<NbNetProfile>2</NbNetProfile>
<NetworkName>3</NetworkName>
<ProfBrowser>3</ProfBrowser>
<ProfMMS>3MMS</ProfMMS>
</ProfileHandle>
<NbProfile>2</NbProfile>
<Profile>
<NetworkName>3</NetworkName>
<Editable>no</Editable>
<ProfileName>3</ProfileName>
<URL>http://mobile.three.co.uk/hb/HutchKey</URL>
<Auth>none</Auth>
<Protocol>http</Protocol>
<MTUSize>1440</MTUSize>
<Proxy>
<EnableFlag>off</EnableFlag>
</Proxy>
<PSparam>
<APN>three.co.uk</APN>
</PSparam>
</Profile>
<Profile>
<NetworkName>3</NetworkName>
<Editable>no</Editable>
<ProfileName>3MMS</ProfileName>
<URL>http://mms.um.three.co.uk:10021/mmsc</URL>
<Auth>none</Auth>
<Protocol>http</Protocol>
<MTUSize>1440</MTUSize>
<Proxy>
<EnableFlag>on</EnableFlag>
<ServAddr>mms.three.co.uk</ServAddr>
<Port>8799</Port>
</Proxy>
<PSparam>
<APN>three.co.uk</APN>
</PSparam>
</Profile>
</Connections>
</Settings>
</CustomerData>

It works ok and should do for any device.

I now have WB-AMR on my phone, cheers! :)