C++ DLL in VB - separate instances

Hi all...

I have a little problem I'm hoping to get some help with.

I have a dll written in VB for data access, but its been giving problems lately when installing it on older Windows OSs. So, I've rewritten the functionality into a C++ dll compiled with gcc / g++ on MinGW.

I've exported the functions and I import them in VB as such:

	__declspec (dllexport) BSTR  __stdcall GetVersionNumber()
	{
		char VersionLabel[15] = {0};
		BSTR ReturnValue;
		
		sprintf(VersionLabel, "%u.%u.%u", VersionMajor, VersionMinor, VersionRevision);
	
		ReturnValue = SysAllocStringByteLen (VersionLabel , lstrlen(VersionLabel));
		
		return ReturnValue;
	}

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That gets compiled as such:

g++ -c -DDatabase_dll Database.cpp -I ../Utils -L . -lpq -L ../Utils -lUtils -lOleaut32

g++ -shared -o Database.dll Database.o -Wl,--add-stdcall-alias -L . -lpq -L ../Utils -lUtils -lOleaut32

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and then in VB it gets imported like this:

Private Declare Function GetVersionNumber Lib "Database.dll" () As String

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If I call GetVersionNumber (or any other function), it works 100% and I have no problems. Where the problem comes in is that the orginal Database.dll written in VB still exists, but all functionality was stripped out and replaced by calls to the C++ version.

Thus, the main apps which use the VB version are not affected by the change. They continue to call the VB dll as if it implemented the functions itself. The VB dll is now only a wrapper around the C++ dll.

The problem comes in when I need to call more than one instance of the dll at a time.

Eg,

dim x as Database.classname
set x = new Database.classname

dim y as Database.classname
set y = new Database.classname

x.SQLQuery("SELECT * FROM Table1")
y.SQLQuery("SELECT * FROM Table2")

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This does not result in 2 separate instances of the C++ dll being called. The VB dll seems to create only one instance of the C++ dll so, the query in object y overwrites the query in object x (or I guess it would be more correct to say that object y = object x).

Does anyone know how to solve this? Should I look into com, activex, etc? If so, any pointers on implementing that from a MinGW / gcc / g++ compiler?

Thanks...

John