You can use mailbox creator for that. Also you what Belle device? C7? I got C7 and I installed Delight Custom Firmware (
http://symwld.com/delight/) to it. I mostly use it as car player since it internal FM transmitter and my radio tape deck failed. That also includes mail creator with it. It can run on Nokia 807, 603, 701, 700, Oro, X7, E7, C6-01, C7 and N7. Only downside it only got english localization. You should also refrain from using language packs from older builds. I asked about that from developer via email and here was his answer:
I'll definetly check out Mailbox Creator
I daily drive a Nokia 701, along with an Iphone. 701 also has an FM transmitter, but I've never really found much use of it. I use wired headphones for listening to music and bluetooth for the car audio and bt speakers.
But with bluetooth I noticed there is a weird
click sound sometimes, on avarage once for 2-minute song, when I use a Symbian Belle Nokia with all
bluetooth audio devices, this is not the case with Symbian Anna and older. I have quite a bunch of Nokia phones which I treat as collectables. 808, 701, 603, N8 updated to Belle all have this issue and N8(before an update) and 500 on Anna does not.
Do you also get that weird bluetooth audio click on your C7?
I've actually made a custom Polish localization for the latest Delight for 701.
Never published it cause I couldn't get some parts like theme choosing ui in settings, camera app, equalizer, and homescreen properly translated
Based my work on this custom Polish delight for 808, it would be harder if one doesn't exist for Finnish (at least for a different phone model)
http://nokiahacking.pl/delight-1-8-pl-vt34716.htm
Don't remember if 1.8 for 808 is the latest or not.
I extracted the firmware with Nokia Cooker looked up differences with Winmerge betweem the Polish 808 Delight firmware and Delight english 808 firmware,
next copied over the language files that were different between Polish 808 Delight firmware and Delight english 808 from the original Polish 701 firmware to 701 Delight firmware.
And I got those that didn't work from 808 custom Polish delight instead of original Polish 701 firmware I saved a list of those (may also include files that I had to revert to english):
Directory: C:\Users\user\Desktop\jezykowe z 808
[32;1mMode LastWriteTime Length Name[0m
[32;1m---- ------------- ------ ----[0m
d---- 2025-02-10 18:05 apps
d---- 2025-02-10 18:07 qt
-a--- 2025-02-10 12:17 48846 avkon.r27
-a--- 2025-02-10 12:17 3130 connuiutilsnotif.r27
-a--- 2025-02-10 12:17 3511 Converter.r27
-a--- 2025-02-10 12:17 701 filelist.r27
-a--- 2025-02-10 12:17 2757 gspeninputpluginrsc.r27
-a--- 2025-02-10 12:17 13540 ias.r27
-a--- 2025-02-10 12:17 65 iractiveidle.r27
-a--- 2025-02-10 12:17 2289 mediafilelist.r27
-a--- 2025-02-10 12:17 4882 mpxmetadataeditordialog.r27
-a--- 2025-02-10 12:17 188 PhoneServer.r27
-a--- 2025-02-10 12:17 458 photoeditorplugin.r27
-a--- 2025-02-10 12:17 597 profileeng.r27
-a--- 2025-02-10 12:17 262 profilerpublisherres.r27
-a--- 2025-02-10 12:17 2273 psln.r27
-a--- 2025-02-10 12:17 526 satinfo.r27
-a--- 2025-02-10 12:17 873 ScreenSaverAnimPlugin.r27
-a--- 2025-02-10 12:17 2694 setwizemailview.r27
-a--- 2025-02-10 12:17 247 SlideshowPlugin.r27
-a--- 2025-02-10 12:17 439 stagegspluginrsc.r27
-a--- 2025-02-10 12:17 5164 videoeditor.r27
-a--- 2025-02-10 12:17 325 videoeditorplugin_internal.r27
-a--- 2025-02-10 12:17 400 wlansettingsui.r27
Directory: C:\Users\user\Desktop\jezykowe z 808\apps
[32;1mMode LastWriteTime Length Name[0m
[32;1m---- ------------- ------ ----[0m
-a--- 2025-02-10 12:17 5234 Blid.r27
-a--- 2025-02-10 12:17 1294 Drawing.r27
-a--- 2025-02-10 12:17 5036 fmradio.r27
-a--- 2025-02-10 12:17 127 homescreen.r27
-a--- 2025-02-10 12:17 7241 internetradio.r27
-a--- 2025-02-10 12:17 7482 internetradio_tc.r27
-a--- 2025-02-10 12:17 11070 issearch.r27
-a--- 2025-02-10 12:17 397 LmkMsgViewer.r27
-a--- 2025-02-10 12:17 8011 logs.r27
-a--- 2025-02-10 12:17 3312 MIFEditor.r27
-a--- 2025-02-10 12:17 5674 mpxcollectionviewhg.r27
-a--- 2025-02-10 12:17 4882 mpxmetadataeditordialog.r27
-a--- 2025-02-10 12:17 1159 mpxscreensaverplugin.r27
-a--- 2025-02-10 12:17 94 noteswidgetre1.r27
-a--- 2025-02-10 12:17 200 notifierharvesterstrings.r27
-a--- 2025-02-10 12:17 1064 notifierlistapplication.r27
-a--- 2025-02-10 12:17 390 notifierwidgetsettings.r27
-a--- 2025-02-10 12:17 262 profilerpublisherres.r27
-a--- 2025-02-10 12:17 70 qmlmirror.r27
-a--- 2025-02-10 12:17 1116 slidewizard.r27
-a--- 2025-02-10 12:17 2411 vcxhgmyvideos.r27
-a--- 2025-02-10 12:17 5164 videoeditor.r27
-a--- 2025-02-10 12:17 228 videoservices.r27
-a--- 2025-02-10 12:17 81 webviewselector.r27
-a--- 2025-02-10 12:17 786 widgetmanagerview.r27
-a--- 2025-02-10 12:17 1940 winRAR.r27
Directory: C:\Users\user\Desktop\jezykowe z 808\qt
[32;1mMode LastWriteTime Length Name[0m
[32;1m---- ------------- ------ ----[0m
d---- 2025-02-10 18:07 translations
Directory: C:\Users\user\Desktop\jezykowe z 808\qt\translations
[32;1mMode LastWriteTime Length Name[0m
[32;1m---- ------------- ------ ----[0m
-a--- 2025-02-10 12:17 12252 gallery_pl.qm
-a--- 2025-02-10 12:17 5004 shareui_pl.qm
|
And I had to leave some which I mentioned earlier
C7 is closer to N8, so I would look for Finnish custom delight for N8 rather than 808
r files are like mui for Windows. r27 are Polish files Finland will have some other r number
If you want to experiment with Nokia Cooker (be wary it's possible to brick a phone with bad firmware, so it's best to experiment on an already half-broken one), send me a PM and I'll send you my 701 Polish firmware so you can compare it with English 701 delight and see what exactly was changed as I already don't remember some things I did

.